A transformers performer poses for photo during the 2014 Beijing International Automotive Exhibition at China International Exhibition Center in Beijing, China, on April 21, 2014. More than 2,000 automotive enterprises from 14 countries and regions participated in the show. (Photo by Feng Li/Getty Images)

A man dressed in a traditional ancient Roman costume eats breakfast in a cafe before a parade along the ancient Roman ruins of the Colosseum, Circus Maximus and the Roman Forum to celebrate the festivities of the Christmas of Rome, on April 21, 2014. Legend says that Rome was founded by Romulus on April 21, 753 BC in an area surrounded by seven hills. Every year the city celebrates the Birth of Rome with parades and fighting in costume, re-enacting the deeds of the great ancient Roman Empire. (Photo by Andrew Medichini/Associated Press)

A woman holds up the small recipe book by Sri Lanka's iconic chef Publis Silva in Colombo April 24, 2014. The book is about 1cm by 1 cm (0.39 inch by 0.39 inch) and weight about 5 milligrams (0.00018 ounce), and there be 40 copies of it. (Photo by Dinuka Liyanawatte/Reuters)

Filipino candidate's of the Miss Earth-Philippines beauty pageant hold placards to mark Earth Day at the Solaire Resort and Casino in Manila, Philippines, April 22, 2014. A total of 51 environmentally aware and concerned Filipino young ladies will compete to represent the Philippines at the Miss Earth beauty pageant. Now in its fourteenth year, Miss Earth is a pioneering beauty pageant that serves as a vehicle for environmental advocacy. Coronation night will be on May 11. (Photo by Ritchie B. Tongo/EPA)

A boy climbs out of a charred shanty as he collects reusable materials after a fire razed through a slum area in Caloocan City, Metro Manila April 21, 2014. The fire left one dead and displaced an estimated 1,000 families and at least 400 houses were destroyed during the fire, a local media reporte. (Photo by Romeo Ranoco/Reuters)

A worker rides a bicycle in a container area at a port in Tokyo April 21, 2014. Japan suffered its worst annual trade deficit in March as exports growth slowed to its weakest in a year, suggesting a rapid loss of economic momentum that may prompt policy makers into early action as a national sales tax hike puts more strain on growth. (Photo by Toru Hanai/Reuters)

Former depositors at PrivatBank crowd in front the bank in Simferopol, Crimea, to receive compensation for savings lost as a result of the lender's closure by Russian banking authorities, on April 23, 2014. Operations at PrivatBank and three other Ukrainian banks on the peninsula have been shut down following Russia's annexation of the territory. (Photo by Alexander Polegenko/Associated Press)

Chen Qingzu, 56, stands in a small room with the walls and ceiling covered in bras he collected, in Sanya, Hainan province April 22, 2014. Chen has collected about 5,000 bras over 20 years after touring more than 30 different colleges around the country for public benefit activities aiming to raise awareness of breast cancer, local media reported. (Photo by Reuters)

An elderly woman walks in the center of Slovyansk, eastern Ukraine, Wednesday, April 23, 2014. Pro-Russian gunmen in eastern Ukraine admitted on Wednesday that they are holding American journalist Simon Ostrovsky, saying he was suspected of unspecified “bad activities”. (Photo by Sergei Grits/AP Photo)

A handout picture provided by the Indonesian Air Force shows Australian Matt Christopher (C) is escorted away by Indonesian military officers at Ngurah Rai International Airport in Bali, Indonesia, 25 April 2014. An unruly passenger and not a hijack caused a Virgin Australia passenger jet to report a problem when it landed at Denpasar airport in Bali, the airline said on 25 April 2014. (Photo by EPA/HO)

A local resident reacts after looking at the bodies of victims of a gunfight overnight near the city of Slaviansk, April 20, 2014. A fatal gun battle overnight near the eastern Ukrainian city of Slaviansk shows that the Ukrainian authorities are failing to rein in armed extremists, Russia's foreign ministry said on Sunday. (Photo by Gleb Garanich/Reuters)

South Korean rescue workers operate where the capsized passenger ship Sewol sank, as fishing boats emit light during the night rescue operation in Jindo April 22, 2014. The Sewol ferry sank last Wednesday on a routine trip south from the port of Incheon to the traditional honeymoon island of Jeju. Of the 476 passengers and crew on board, 339 were children and teachers on a high school outing. Only 174 people have been rescued and the remainder are all presumed to have drowned. (Photo by Issei Kato/Reuters)

An anti-government protester fires a homemade mortar toward police officers during a demonstration in which masked youths battled police and blocked a main highway in Caracas, Venezuela, on April 21, 2014. Protests against the government of President Nicolas Maduro have led to violence that has killed at least 41 people since early February, according to official figures. The dead have been from both sides of the South American nation’s political divide, as well as from security forces. (Photo by hristian Veron/Reuters)

Vietnam veteran Fred Downs gives a thumbs up during a demonstration of modular prosthetic arm technology developed by the Defense Advanced Research Projects Agency (DARPA) at the Pentagon in Washington April 22, 2014. (Photo by Kevin Lamarque/AFP Photo)

An anti-government protester, wearing a Guy Fawkes mask, stands with a shield near flames from Molotov cocktails during riots in Caracas, Venezuela, on April 20, 2014. Masked youths battled police and marchers demanded the “resurrection” of democracy on a volatile Easter Sunday in Venezuela. (Photo by Jorge Silva/Reuters)

An armed man stands guard outside a regional government building seized by pro-Russia militants in Kramatorsk, eastern Ukraine, on April 22, 2014. An international agreement to avert wider conflict in Ukraine was faltering Monday, with pro-Moscow separatist gunmen showing no sign of surrendering the government buildings they have seized. (Photo by Baz Ratner/Reuters)

An anti-riot policeman grabs a banner from protesters as they are hit with a water cannon during a protest against the upcoming visit of U.S. President Barack Obama next week, in front of the U.S. embassy in Manila April 23, 2014. (Photo by Romeo Ranoco/Reuters)

Masked Sunni gunmen pray during a patrol outside the city of Falluja April 23, 2014. Government forces are fighting rebellious Sunni tribes and an al-Qaeda splinter group, the Islamic State in Iraq and the Levant (ISIL), in western Anbar province. (Photo by Reuters/Stringer)

A group of tourists sit during a bullfight master class for schoolchildren at the Maestranza bullring in the Andalusian capital of Seville, southern Spain, April 23, 2014. (Photo by Marcelo del Pozo/Reuters)

The B-31 Iceberg is seen before, (top) on October 28, 2013 and after separating on November 13, 2013, from a rift in Antarctica's Pine Island Glacier in this NASA Earth Observatory handout image. Scientists are monitoring an unusually large iceberg – roughly six times the size of Manhattan – that broke off from an Antarctic glacier and is heading into the open ocean, although not in an area heavily navigated by ships. (Photo by Holli Riebeek/Reuters/NASA Earth Observatory)

A boy runs in front of the “Serpent d'ocean” (Ocean snake) in Saint-Brevin-les-Pins, western France, April 24, 2014. Ocean Serpent is a giant aluminium sea serpent skeleton by the Chinese artist Huang Yong Ping. (Photo by Stephane Mahe/Reuters)

An anti-government protester, wearing a mask in the colors of the Venezuelan flag, stands at a barricade during riots in Caracas, the nation’s capital, on April 20, 2014. Masked youths battled police, protesters burned and hung effigies of President Nicolas Maduro from lampposts as marchers demanded the “resurrection” of democracy on a volatile Easter Sunday in Venezuela. (Photo by Jorge Silva/Reuters)

Civilians, who survived what activists said were barrel bombs dropped by forces loyal to Syria's President Bashar al-Assad, run in Aleppo's al-Shaar district April 24, 2014. (Photo by Ahmad Othman/Reuters)

Girls pan for gold in a stream next to a local mine near the village of Game, about 230 kilometres north of the capital Bangui April 24, 2014. (Photo by Siegfried Modola/Reuters)

An E-Fan aircraft is seen on the tarmac for its first public flight during the e-Aircraft Day at the Bordeaux Merignac airport, southwestern France, April 25, 2014. The all-electric plane E-Fan, developed by Airbus Group, is 6.7 metres long with a 9.5 metre wingspan, and has two electric turbines with a total power of 60kW. Its has a cruising speed of 160 km/h (99 mph) for about an hour of flight time. (Photo by Regis Duvignau/Reuters)

An explosion is seen during a car bomb attack at a Shi'ite political organisation's rally in Baghdad, April 25, 2014. A series of explosions killed 18 people at a Shi'ite political organisation's rally in Iraq on Friday, police and medical sources said. The militant group, Asaib Ahl Haq (League of the Righteous), introduced its candidates for elections on April 30 at the rally in eastern Baghdad. Three bombs exploded in succession as people were leaving, Reuters reporters at the scene said. (Photo by Thaier al-Sudani/Reuters)

Anti-government protesters jump and step on a banner of Banco de Venezuela after bringing down the banner during riots in Caracas April 20, 2014. Masked youths battled police, protesters burned and hung from lamp-posts effigies of President Nicolas Maduro and marchers demanded the “resurrection” of democracy on a volatile Easter Sunday in Venezuela. (Photo by Jorge Silva/Reuters)

Boys play soccer on the main street of Kilometre 5 (PK5), a predominately Muslim neighbourhood of the capital Bangui April 23, 2014. (Photo by Siegfried Modola/Reuters)

A Brazilian Police Special Forces member aims his gun as a man walks past with his arms up during a violent protest in a favela near Copacabana in Rio de Janeiro, Brazil on April 22, 2014. Violent protests broke out in Rio's landmark beachfront district, Copacabana, following the death of a resident last weekend during clashes with the Army in a nearby favela. (Photo by Christophe Simon/AFP Photo)

A student holds a pair of banderillas during a bullfight master class for schoolchildren at the Maestranza bullring in the Andalusian capital of Seville, southern Spain, April 23, 2014. (Photo by Marcelo del Pozo/Reuters)

Animal rights activists covered with fake blood sit on the floor during a protest against the use of animals in research to mark World Day for Animals in Laboratories in central Madrid April 24, 2014. The sign reads, “How many rabbits do your shampoo kill?”. (Photo by Andrea Comas/Reuters)

A man throws water on a woman as part of traditional Easter celebrations in Holloko, east of Budapest, April 21, 2014. Locals from the World Heritage village of Holloko celebrate Easter with the tradition “watering of the girls”, a Hungarian tribal fertility ritual rooted in the area's pre-Christian past. (Photo by Bernadett Szabo/Reuters)

Filipino electric workers restore power following an overnight fire that razed a slum area in Caloocan city, east of Manila, the Philippines, 21 April 2014. One person died, one more is missing, and thousands of families lost their homes on Easter Sunday after several fire hit residential areas in Metro Manila. Investigators said the result of an initial investigation pointed to electrical short circuit as the cause of the blaze. (Photo by Francis R. Malasig/EPA)

Supporters of Hindu nationalist Narendra Modi, the prime ministerial candidate for India's main opposition Bharatiya Janata Party (BJP), climb over the poles of a temporary tent to get a glimpse of Modi during an election campaign rally at Mathura in the northern Indian state of Uttar Pradesh April 21, 2014. Around 815 million people have registered to vote in the world's biggest election – a number exceeding the population of Europe and a world record – and results of the mammoth exercise, which concludes on May 12, are due on May 16. (Photo by K. K. Arora/Reuters)