A Palestinian youth practices his Parkour skills over the ruins of houses, that witnesses said were destroyed during a 50-day war last summer in the Shejaia neighborhood east of Gaza City May 12, 2015. (Photo by Mohammed Salem/Reuters)

Jennifer Perez, 19, pours water on her friend Marijose Sanchez, 19, as they try to cool off while sunbathing during a hot spring day in Madrid, Spain, May 12, 2015. Temperatures will rise up to 40 degrees Celsius (104 fahrenheit) in some parts of Spain, the Spanish Agency of Meteorology (AEMET) said on Tuesday. (Photo by Susana Vera/Reuters)

A Clear Creek Independent School District school bus is pulled out of a house it crashed into in the Oaks of Clear Creek neighborhood in League City, Texas, Tuesday, May 12, 2015. The driver, an aide, and an 11-year-old student were on board at the time of the crash and were all transported to the hospital with minor injuries. Sgt. Tammy Spencer says a woman and her three children were in the house but not injured. (Photo by Kevin M. Cox/AP Photo/The Galveston County Daily News)

Visitors walk past near a British Austin A40 post-war saloon car dating back to 1947 during Myanmar's first ever classic cars show in Yangon, Myanmar, 10 May 2015. Around 25 classic cars ranging from 1928 participated in the show. (Photo by Lynn Bo Bo/EPA)

Faithful throw in the air a jersey and two hats as Pope Francis leaves at the end of his weekly general audience in St. Peter's Square at the Vatican, Wednesday, May 13, 2015. (Photo by Alessandra Tarantino/AP Photo)

Riot police hold up their shields to make a corridor for River Plate players exit the stadium after their Copa Libertadores soccer match with Boca Juniors was suspended after the first half in Buenos Aires, Argentina, Friday, May 15, 2015. Police are investigating after the high-profile match was stopped when visiting players were sprayed by fans with an eye irritant believed to be pepper spray or mace. The match turned to chaos when River players, entering the field for the second half, came out of a temporary tunnel rubbing their eyes and pulling their shirts over their faces. The stadium has been closed so investigators can “gather evidence”. (Photo by Victor R. Caivano/AP Photo)

Marcelo Gallardo coach of Argentina's River Plate leaves the field under the protection of police shields after a Copa Libertadores soccer match against Boca Juniors was cancelled in Buenos Aires, Argentina, Friday, May 15, 2015. Conmebol authorities and referee Dario Herrera canceled the game after pepper spray was thrown from the stands towards River Plate players before the start of the second half of the game. (Photo by Natacha Pisarenko/AP Photo)

Darya Klishina of Russia competes in the women's long jump at of the Golden Grand Prix track and field in Kawasaki, near Tokyo, Sunday, May 10, 2015. (Photo by Shizuo Kambayashi/AP Photo)

A man takes part in the celebrations, to mark Liberia being an Ebola free nation in Monrovia, Liberia, Monday, May 11, 2015. Liberians are gathering in the streets of the capital to celebrate the end of the Ebola epidemic in this West African country. Monday's festivities come after the World Health Organization declared over the weekend that Liberia was finally Ebola-free. (Photo by Abbas Dulleh/AP Photo)

A man on stilts walks through the streets during an official celebration of the country being declared Ebola-free in Monrovia, Liberia, May 11, 2015. Liberia was declared free from Ebola by the government and the World Health Organisation (WHO) on Saturday after 42 days without a new case of the virus, which killed more than 4,700 people there during a year-long epidemic. (Photo by James Giahyue/Reuters)

Competitors take part in a coaching marathon along the “Long Walk” during the third day of the Royal Windsor Horse Show at Windsor Castle, Windsor, England, Friday, May 15, 2015. (Steve Parsons/AP Photo/PA Wire)

Shiite pilgrims beat themselves and cover themselves with mud as they march toward the Imam Mousa al-Kazim shrine to commemorate the anniversary of the imam's death in Baghdad, Iraq, Monday, May 11, 2015. The anniversary of the 8th-century imam's death draws tens of thousands of Shiites from all walks to converge on his golden-domed shrine in northern Baghdad. The pilgrims typically march to the shrine while hundreds of tents are erected to offer them free food, drinks and services. (Photo by Hadi Mizban/AP Photo)

Kansas City Royals' Lorenzo Cain throws a ball to fans during a rain delay in the ninth inning of a baseball game against the Detroit Tigers, Sunday, May 10, 2015, in Detroit. (Photo by Carlos Osorio/AP Photo)

Myanmar models wearing traditional dresses pose for photo near old cars displayed at the first Myanmar Classic Car Show organized by Myanmar Classic Car Club at Myanmar Culture Valley Saturday, May 9, 2015, in Yangon, Myanmar. (Photo by Khin Maung Win/AP Photo)

Visitors walk past 1964 model Cadillac DeVille displayed at the first Myanmar Classic Car Show organized by Myanmar Classic Car Club at Myanmar Culture Valley Saturday, May 9, 2015, in Yangon, Myanmar. (Photo by Khin Maung Win/AP Photo)

A Myanmar model wearing traditional dress rubs her face as she prepares to pose for photo near motorbikes displayed at the first Myanmar Classic Car Show organized by Myanmar Classic Car Club at Myanmar Culture Valley Saturday, May 9, 2015, in Yangon, Myanmar. (Photo by Khin Maung Win/AP Photo)

A woman walks by an electronic stock board of a securities firm in Tokyo, Friday, May 15, 2015. Shares in Asia were uneven on Friday as the big markets in Japan and Hong Kong got a lift from the rebound on Wall Street, but weak data dragged Chinese shares lower. (Photo by Koji Sasahara/AP Photo)

A child looks up at Titan the Robot performing in Bucharest, Romania, Monday, May 11, 2015. Titan the robot is produced by British company Cyberstein Robots Ltd and gained world recognition in pop videos dancing alongside artists such as Rihanna in music videos. (Photo by Vadim Ghirda/AP Photo)

People watch Titan the Robot performing in Bucharest, Romania, Monday, May 11, 2015s. (Photo by Vadim Ghirda/AP Photo)

Two cows fight during the traditional annual “Combats de Reines” (“Battle of the Queens”), a cow fight in Aproz, Western Switzerland, Sunday, May 10, 2015. Each year before taken to the alpine pastures, the cows test their strength and fight for the herd's leadership. The competition continues until a new queen has forced all the other cows to retreat. (Photo by Jean-Christophe Bott/Keystone via AP Photo)

The mens riders warm up prior to the finals in the UCI BMX Supercross World Cup held at the Papendal Outdoor Olympic Training Centre on May 10, 2015 in Arnhem, Netherlands. (Photo by Dean Mouhtaropoulos/Getty Images)

Masked penitents holds their crosses during spring “Romeria Cruceros de Arce”, while they walk alongside Villanueva de Arce and Roncesvalles northern Spain Sunday, May 10, 2015. Every year on the second Sunday in spring, people with crosses march from their small Pyrenees towns to Roncesvalles Church in tribute of the Virgin. (Photo by Alvaro Barrientos/AP Photo)

Residents along Manila Bay play in the waves created by nearby Typhoon Noul on May 10, 2015 as it approaches the northern Philippines. More than 2,000 people were fleeing their homes as Typhoon Noul approached the northern Philippines on May 10, triggering warnings of possible flash floods, landslides and tsunami-like storm surges. (Photo by Jay Directo/AFP Photo)

A worker walks up a pile of rice at a warehouse of the Philippines National Food Authority in Manila May 12, 2015. The state grains agency continues stockpiling ahead of the lean harvest season beginning July, aiming to keep local prices of the staple food affordable to poor Filipinos while bracing for the impact of the dry season on rice harvest. A closely watched forecast by Japan on Tuesday confirmed the El Nino weather phenomenon's return this year. (Photo by Romeo Ranoco/Reuters)

The Victory Belles, from the National WWII Museum, perform at the National Ethnic Coalition of Organizations' 2015 Ellis Island Medal of Honor awards ceremony on Ellis Island, Saturday, May 9, 2015. NECO honored 101 recipients, including journalist Meredith Vieira, New York Yankees legend Mariano Rivera, Washington, D.C. Police Chief Cathy L. Lanier and 11 members of the U.S. military. NECO's mission is to honor and preserve the diversity of the American people and to foster tolerance, respect and understanding among religious and ethnic groups. (Photo by Diane Bondareff/Invision for NECO/AP Images)

Vacuum cleaners sit on display during a liquidation sale at the closed Riviera hotel and casino Wednesday, May 13, 2015, in Las Vegas. The sale will be open to the general public on Thursday. (Photo by John Locher/AP Photo)

A woman dressed as a member of British Home Guard from World War II laughs as she attempts to unfurl her tangled dog leads on the first day of the Haworth 1940s Weekend in the village of Haworth, Northern England on May 15, 2015. Each year the village celebrates the 1940's with a programme of events and a re-enactment of the period in the village. (Photo by Oli Scarff/AFP Photo)

A young Thai man jumps in the air and cheers as his rocket takes off at the Bun Bang Fai Rocket Festival on May 10, 2015 in Yasothon, Thailand. During the Bun Bang Fai rocket festival, Thai residents launch enormous home-made rockets into the air to gain Buddhist merit and to celebrate the beginning of the rainy season. (Photo by Taylor Weidman/Getty Images)

Thai men cheer as their rocket takes off at the Bun Bang Fai Rocket Festival on May 10, 2015 in Yasothon, Thailand. (Photo by Taylor Weidman/Getty Images)

Thai teammates wait for a rocket to take off before mounting their rocket at the launching area at the Bun Bang Fai Rocket Festival on May 10, 2015 in Yasothon, Thailand. (Photo by Taylor Weidman/Getty Images)

A maltese dog plays with a gnome in Germany's Garden Gnome Park (Zwergen-Park) in Trusetal, central Germany, Thursday, May 14, 2015. Every year up to 100,000 tourists visit the Garden Gnome Theme Park. The park shows more than 2,500 garden gnomes. (Photo by Jens Meyer/AP Photo)

The 50 meter long and 30 meter high Artron Wall on show during the 11th China (Shenzhen) International Cultural Industries Fair (ICIF) at the Artron Art Center on May 14, 2015 in Shenzhen, China. The Artron Wall on show at 2015 Shenzhen's cultural industry fair is 50 meters in length and 30 meters high housing over ten hundred thousand art books which is said to be the world's largest Artron Wall. (Photo by ChinaFotoPress/Getty Images)

An ethnic Rohingya young girl holds a balloon of Russian cartoon character “Masha” at a temporary shelter in Lapang, Aceh province, Indonesia, Thursday, May 14, 2015. More than 1,600 migrants and refugees from Myanmar and Bangladesh have landed on the shores of Malaysia and Indonesia in the past week and thousands more are believed to have been abandoned at sea, floating on boats with little or no food after traffickers literally jumped ship fearing a crackdown. (Photo by Binsar Bakkara/AP Photo)

Models present a creation from the Cruise 2016 collection by Christian Dior fashion house at the Palais Bulles in Theoule-sur-Mer, France, 11 May 2015. Belgian designer Raf Simons hosts his 2016 resort show for Dior at Pierre Cardin's iconic house, near Cannes, ahead of the 68th annual Cannes Film festival, which will run from 13 to 25 May. (Photo by Sebastien Nogier/EPA)

A US soldier prepares an armoured vehicle for the official opening ceremony of the joint US-Georgia military exercise “Noble Partner 2015” at the military base of Vaziani outside Tbilisi, Georgia, 11 May 2015. Exercise Noble Partner is a bilateral effort focused on enhancing US and Georgian NATO Response Force interoperability in the context of military-to-military relationships, the United States Army Europe says on its website. It involves some 600 Georgian and US service members. (Photo by Zurab Kurtsikidze/EPA)

A participant poses during the Istanbul Zombie Walk in Nisantasi Park, in Istanbul, Turkey, 10 May 2015. (Photo by Sedat Suna/EPA)

An aerial view taken from a sea plane shows Swiss pilot and original Jetman Yves Rossy (front) and Vince Reffett flying over Dubai's Palm Island, Dubai, United Arab Emirates May 12, 2015. (Photo by Lara Sukhtian/Reuters)

An aerial view taken from behind airplane's window glass shows Swiss pilot and aviation enthusiast Yves Rossy(Bottom) known as the Jetman and French Vince Reffett (Up) flying over Jumeirah Beach Residence (also known as JBR) in Dubai, United Arab Emirates on 12 May 2015. (Photo by Ali Haider/EPA)

An aerial view taken from behind airplane's window glass shows Swiss pilot and aviation enthusiast Yves Rossy (L) known as the Jetman and French Vince Reffett (R) flying over the beach in Dubai, United Arab Emirates on 12 May 2015. (Photo by Ali Haider/EPA)

An aerial view taken from a sea plane shows Swiss pilot and original Jetman Yves Rossy (front) and Vince Reffett flying over Dubai's Palm Island, United Arab Emirates May 12, 2015. (Photo by Lara Sukhtian/Reuters)

A U.S. Army serviceman helps a Romanian child look through the scope of a machine-gun in Ploiesti, Romania, Wednesday, May 13, 2015. Members of the US military took part in an exercise dubbed the Cavalry March, a drive from southern Romania to a training range in the central region of Transylvania, involving 400 servicemen and 80 armored combat vehicles. (Photo by Vadim Ghirda/AP Photo)

A US serviceman holds a pilot helmet for child posing on an Apache attack helicopter in Ploiesti, Romania, Wednesday, May 13, 2015. (Photo by Vadim Ghirda/AP Photo)

Yulia Kozyreva, a circus artist, performs with a tiger during a show in Ukraine's National Circus in Kiev, Ukraine, Sunday, May 10, 2015. (Photo by Efrem Lukatsky/AP Photo)

A man is detained by state police after workers of tomato farm labor camps allegedly invaded private property, according to state police, in the town of San Quintin, on Mexico's Baja peninsula, Saturday, May 9, 2015. Dozens of workers were injured in the clash, some seriously, according to a spokesman of the National, State and Municipal Alliance for Social Justice. Farm workers have been protesting for months demanding higher wages and better working conditions. (Photo by Roberto Armocida/La Jornada Baja California via AP Photo)

Yang Shijun, 45-year-old manager of a construction material company, flies his homemade plane during a test run in Changchun, Jilin province, China, May 9, 2015. Yang spent almost 100,000 yuan (16,098 USD) and over one year to make the 5-metre-long, 9.5-metre-wide plane, as a tribute to his father, who passed away in 2011 and had been a pilot for 29 years, local media reported. (Photo by Reuters/Stringer)

Emergency personnel work the scene of a train wreck, Tuesday, May 12, 2015, in Philadelphia. An Amtrak train headed to New York City derailed and crashed in Philadelphia. (Photo by Joseph Kaczmarek/AP Photo)

A gaggle of geese, including three goslings, make the plunge into the Noble Park pond Sunday, May 10, 2015, as park patrons enjoy the sunny afternoon in Paducah. (Photo by John Paul Henry/The Paducah Sun via AP Photo)

Prince Harry sits with pupils at Halfmoon Bay School in Oban as he leaves on May 11, 2015 in Stewart Island, New Zealand. Prince Harry is in New Zealand from May 9 through to May 16 attending events in Wellington, Invercargill, Stewart Island, Christchurch, Linton, Whanganui and Auckland. (Photo by Chris Jackson/Getty Images)

Shaven-headed boys hold lanterns during a lighting ceremony to celebrate Buddha's upcoming birthday on May 25 at the Jogye Temple in Seoul, South Korea Wednesday, May 13, 2015. Nine children entered the temple to have an experience of monks' life for two weeks. (Photo by Ahn Young-joon/AP Photo)

Ranchers wade chest deep in water while trying to herd cattle from a swollen creek near Lake Mexia, Monday, May 11, 2015 near Mexia, Texas. Heavy rains has flood the small community forcing many residents leaving near the lake to leave their homes. The cattle eventually made it to higher ground. (Photo by Rod Aydelotte/AP Photo/Waco Tribune Herald)

The Royal Air Force Red Arrows fly in formation over London for VE Day commemorations on May 10, 2015 in England. The 70th anniversary of Victory in Europe, when World War II ended in 1945, is being commemorated with services and parades. Queen Elizabeth II attended a service of thanksgiving at Westminster Abbey. (Photo by Peter Macdiarmid/Getty Images/WPA Pool)