A devotee holds incense sticks while celebrating the Sindoor Jatra Festival on April 15, 2015 in Thimi, Nepal. Sindoor Jatra Festival is celebrated each year in Thimi, on the outskirts of Kathmandu, to welcome the Nepali New Year and celebrate the coming of spring. During the Festival, devotees are smeared with vermillion powder and 30 chariots containing the images of several gods and goddesses are carrying by the devotees around the town, while others sing, dance and play musical instruments. (Photo by Omar Havana/Getty Images)

Participants wearing superhero costumes attend the World DC Comics Super Heroes event in San Martin de Valdeiglesias, near Madrid, April 18, 2015. To celebrate the anniversary of the publication of the very first Superman story, DC Comics are asking fans to help set a new world record for the largest global gathering of people dressed as DC Comics Super Heroes. (Photo by Andrea Comas/Reuters)

South Korean traditional bow artisan Kwon Yeong-Hak works on a bow in his workshop in Yecheon-gun, Gyeongsangbuk-do, South Korea, 26 February 2015. Kwon Yeong-Hak still crafts his bows in the traditional way, carrying on a four-generation family business. The Gakgung bow, of which Kwon is one of the last remaining artisans, is unique to Korea, and is constructed with a variety of materials, including water buffalo horn, oak, bamboo and cattle spinal sinew. A ban on the import of water buffalo horns has put the Gakgung tradition at risk. (Photo by Jeon Heon-Kyun/EPA)

A female Syrian soldier from the Republican Guard commando battalion drives a tank during clashes with rebels in the restive Jobar area, in eastern Damascus, on March 25, 2015. The female battalion, which was created nearly a year ago, consists of 800 female soldiers who are positioned in the suburbs of the Syrian capital where they monitor and secure the frontlines with snipers, rockets and machine guns. (Photo by Joseph Eid/AFP Photo)

A woman (L) places flowers at a grave next to a mummified body during exhumation works at the General Cemetery in Guatemala City, April 15, 2015. If a lease on a grave has expired or not been paid, grave cleaners will break open the crypts to remove and rebury the bodies. Any remains that have not been claimed are packed into plastic bags, labeled and stored in mass graves. Bodies that have been stored in the upper crypt are exposed to dry and sunny conditions which means they do not decompose and instead become mummified. (Photo by Jorge Dan Lopez/Reuters)

A woman strikes a police truck with her hand during a protest march in Santiago, Chile, Thursday, April 16, 2015. Thousands of students marched through the streets of Chile's capital to protest recent corruption scandals and to complain about delays in a promised education overhaul. While it was largely peaceful, violence broke out at the end when hooded protesters threw rocks and gasoline bombs at police. (Photo by Luis Hidalgo/AP Photo)

A general view shows solar panels to produce renewable energy at the photovoltaic park in Les Mees, in the department of Alpes-de-Haute-Provence, southern France March 31, 2015. The solar farm of the Colle des Mees, the biggest in France, consists of 112,780 solar modules covering an area of 200 hectares of land and representing 100 MW of power. (Photo by Jean-Paul Pelissier/Reuters)

A Kenyan soldier takes cover as shots are fired in front of Garissa University in Garissa town, located near the border with Somalia, some 370km northeast of the capital Nairobi, Kenya, 02 April 2015. At least 15 people have been killed and some 60 were injured in an attack carried out by Somalia's Islamist militant group al-Shabab, according to local media reports. (Photo by Dai Kurokawa/EPA)