In this handout photo provided by the U.S. Navy, the USS Stout launches a Tomahawk missile in support of Operation Odyssey Dawn March 19, 2011. This was one of approximately 110 cruise missiles fired from U.S. and British ships and submarines targetting about 20 radar and anti-aircraft sites along Libya's Mediterranean coast.

Men dressed as Vikings lead the torchlight procession as it makes its way along Princess Street for the start of the New Year celebrations December 30, 2011 in Edinburgh, Scotland. Thousands of people joined in the torchlight procession, which is followed by the burning of a Viking long ship, to mark the start of Edinburgh's Hogmanay celebrations. (Photo by Jeff J. Mitchell/Getty Images)

A security exercise takes place along the River Thames on January 19, 2012 in London, England. The exercise including around 44 police officers, 94 military personnel, 15 boats and a Royal Navy Lynx helicopter was conducted by both the Metropolitan Police and the Royal Marines and designed to test their joint capability ahead of the 2012 London Olympic Games. (Photo by Dan Kitwood/Getty Images)

A street artist dances tango in Buenos Aires, Argentina, Tuesday, January 20, 2015. Tango is a partner dance that originated in the 1890's along the Rio de la Plata, the border between Uruguay and Argentina. UNESCO approved in 2009, a joint proposal by the two nations to include the dance in its Intangible Cultural Heritage List. (Photo by Rodrigo Abd/AP Photo)

In this Friday, February 6, 2015 photo, sandhill cranes begin to stir after resting for the night at a roosting location along their winter migration route in Cecilia, Ky. According to counts made by biologists with the Kentucky Fish and Wildlife Resources, about 12,000 of the birds have stopped in Cecilia this week during their winter northward migration on their way to their nesting grounds in the Great Lakes region. (Photo by David Stephenson/AP Photo)

Matthias Broda, inventor and designer of the wooden e-bike, cycles a prototype along a street in Berlin, November 20, 2014. The wooden e-bike produced by German company Aceteam from ash wood, will be launched on the market by spring 2015 and will cost around 3,950 euro (4,950 dollars). The e-bike will be equipped with an 250W e-bike motor for a range of up to 100 kilometer (62 miles) with a rechargeable battery. (Photo by Fabrizio Bensch/Reuters)

Riot police hold their weapons during a protest by supporters of Kenyan opposition National Super Alliance (NASA) coalition, along a street in Nairobi, Kenya on October 11, 2017. Opposition leader Raila Odinga, has called for protests this week, reiterated that he would not take part in a re- run of the presidential election on October 26, 2017 if his demands are not met, as Kenya' s Supreme Court last month overturned the August election of President Uhuru Kenyatta citing “irregularities” in the counting of results. (Photo by Thomas Mukoya/Reuters)

Indian mourners perform a cremation on the roof of a building overlooking The Manikarnika Ghat in Varanasi on August 23, 2016. India's holy city of Varanasi has been forced to halt cremations along the banks of the sacred river Ganges as deadly floods from monsoon rains hit parts of the country, an official said. More than 100,000 people have been forced from their homes in recent days in northern Uttar Pradesh and neighbouring Bihar states as rain-swollen rivers burst their banks. (Photo by Sanjay Kanojia/AFP Photo)