Graduates toss their caps in the air at the conclusion of the commencement ceremony for the U.S. Naval Academy Class of 2015 in Annapolis...Graduates toss their caps in the air at the conclusion of the commencement ceremony for the U.S. Naval Academy Class of 2015 in Annapolis, Maryland May 22, 2015.

Kevin Lamarque/Reuters

Graduates toss their caps in the air at the conclusion of the commencement ceremony for the U.S. Naval Academy Class of 2015 in Annapolis, Maryland on Friday

 European Commission President Jean-Claude Juncker (R) makes a joke with tie-less Greek Prime Minister Alexis Tsipras (L) during the second day of the Eastern Partnership Summit in Riga, Latvia, 22 May 2015

Radek Pietruszka/EPA

European Commission President Jean-Claude Juncker (R) makes a joke with tie-less Greek Prime Minister Alexis Tsipras (L) during the second day of the Eastern Partnership Summit in Riga, Latvia on Friday

A man walks past billboard posters promoting the Yes campaign in favour of same-sex marriage on Friday in Dublin, Ireland. Voters in the Republic of Ireland are taking part in a referendum on legalising same-sex marriage on Friday. The referendum is being held 22 years after Ireland decriminalised homosexuality with more than 3.2m people being asked whether they want to amend the country's constitution to allow gay and lesbian couples to marry. Polling stations opened at 07:00 BST with voting continuing until 22:00 BST and counting due to start on Saturday morning

Charles McQuillan/Getty Images

A man walks past billboard posters promoting the Yes campaign in favour of same-sex marriage on Friday in Dublin, Ireland

Members of the East German Ladies' swimming team leave the new 'King's Cross Pond Club' outdoor swimming pool on Friday in London, England. The 40 metre pool is purified using submerged plants to filter the water and is surrounded by flowers and plants. It is open to members of the public Monday and Friday between 6am and dusk

Dan Kitwood/Getty Images

Members of the East German Ladies’ swimming team leave the new ‘King’s Cross Pond Club’ outdoor swimming pool on Friday in London, England. The 40 metre pool is purified using submerged plants to filter the water and is surrounded by flowers and plants

A Palestinian boy rests on an old armcha...A Palestinian boy rests on an old armchair in front of a dilapidated house on May 22, 2015 in Gaza City

Mohammed Abed/AFP

A Palestinian boy rests on an old armchair in front of a dilapidated house on Friday in Gaza City

 A man and his cart loaded with sacks of vegetables near the Afghan border in Chaman, Pakistan, 22 May 2015. The merchants wait for clearance to cross into Afghanistan with their goods

Akhter Gulfam/EPA

A man and his cart loaded with sacks of vegetables near the Afghan border in Chaman, Pakistan on Friday. The merchants wait for clearance to cross into Afghanistan with their goods

Belgium's Philippe Gilbert celebrates as he crosses the finish line to win the 12th stage of the Giro d'Italia, Tour of Italy cycling race from Imola to Vicenza, Italy, Thursday, May 21, 2015. Alberto Contador extended his overall lead ahead of Fabio Aru to 17 seconds while Philippe Gilbert won the rainy 12th stage of the Giro d'Italia on Thursday

Daniel Dal Zennaro/ANSA/AP

Belgium’s Philippe Gilbert celebrates as he crosses the finish line to win the 12th stage of the Giro d’Italia, Tour of Italy cycling race from Imola to Vicenza, Italy, Thursday

Dunkirk veteran Garth Wright (95) with Royal Navy Wren Lauren Parsons on board the Little Ship the Princess Freda as the Little Ships arrive in Dunkirk, France, to mark the 75th anniversary of Operation Dynamo. PRESS ASSOCIATION Photo. Picture date: Thursday May 21, 2015. Hundreds of fishing boats, pleasure yachts and lifeboats crossed the Channel between May 26 and June 4 1940, to help evacuate Allied forces from the beaches of northern France

Gareth Fuller/PA

Dunkirk veteran Garth Wright (95) with Royal Navy Wren Lauren Parsons on board the Little Ship the Princess Freda as the Little Ships arrive in Dunkirk, France, to mark the 75th anniversary of Operation Dynamo

Supporters of the pro-Kurdish People's Democratic Party (HDP) wait for the appearance Selahattin Demirtas, co-chair of the party to deliver an election campaign speech during a rally in Istanbul, Turkey, Thursday, May 21, 2015, before Turkey's general election on June 7.  The ADP is a small party, but if it gains 10 percent of the vote it will enter parliament as a party, and could change the face of the country's politics

Lefteris Pitarakis/AP

Supporters of the pro-Kurdish People’s Democratic Party (HDP) wait for the appearance Selahattin Demirtas, co-chair of the party to deliver an election campaign speech during a rally in Istanbul, Turkey on Thursday

A jogger passes by the beach huts at Bournemouth Beach in Dorset, which have been decorated in Cath Kidston prints as part of the brand s #RandomActsofKidston campaign

Matt Alexander/PA

A jogger passes by the beach huts at Bournemouth Beach in Dorset, which have been decorated in Cath Kidston prints as part of the brand’s RandomActsofKidston campaign

Rohingya migrants, who recently arrived in Indonesia by boat, carry an IV drip as they help a fellow migrant to walk inside a temporary compound for refugees in Aceh Timur regency...Rohingya migrants, who recently arrived in Indonesia by boat, carry an IV drip as they help a fellow migrant to walk inside a temporary compound for refugees in Aceh Timur regency, Indonesia's Aceh Province May 21, 2015.  Malaysia and Indonesia issued a joint statement on Wednesday saying they will continue to offer international assistance to 7,000 migrants adrift at sea and assist them with "resettlement and repatriation" within a year with international help

Beawiharta/Reuters

Rohingya migrants, who recently arrived in Indonesia by boat, carry an IV drip as they help a fellow migrant to walk inside a temporary compound for refugees in Aceh Timur regency, Indonesia’s Aceh Province on Thursday

French soldiers, part of Operation Sangaris, patrols Bangui la Coquette at "PK0" of the capital

Patrick Fort/AFP

French soldiers, part of Operation Sangaris, patrols Bangui la Coquette at “PK0″ of the capital

People catch a fish on a flooded street after heavy rainfall in Dongguan, Guangzhou province, China

China Daily/Reuters

People catch a fish on a flooded street after heavy rainfall in Dongguan, Guangzhou province, China

Workers clean up an oil slick along the coast of Refugio State Beach in Goleta...Workers clean up an oil slick along the coast of Refugio State Beach in Goleta, California, United States, May 20, 2015. A pipeline ruptured along the scenic California coastline on Tuesday, spilling some 21,000 gallons (79,000 liters) of oil into the ocean and on beaches before it could be secured, a U.S. Coast Guard spokeswoman said

Lucy Nicholson/Reuters

Workers clean up an oil slick along the coast of Refugio State Beach in Goleta, California, United States on Wednesday. A pipeline ruptured along the scenic California coastline on Tuesday, spilling some 21,000 gallons (79,000 liters) of oil into the ocean and on beaches before it could be secured

Iraqi security forces stand guard as residents from the city of Ramadi, who fled their homes as Islamic State (IS) group militants tightened their siege on the last government positions in the capital of Anbar province, wait to cross Bzeibez bridge, on the southwestern frontier of Baghdad, on May 20, 2015. Taking control of Ramadi would constitute the group's most important victory this year in Iraq, and would give the jihadists control of the capitals of two of its largest provinces

Sabah Arar/AFP

Iraqi security forces stand guard as residents from the city of Ramadi, who fled their homes as Islamic State (IS) group militants tightened their siege on the last government positions in the capital of Anbar province, wait to cross Bzeibez bridge, on the southwestern frontier of Baghdad, on Wednesday

A Syrian man carries a body after it was removed from the rubble of buildings following a reported barrel bomb attack by government forces on the Qadi Askar district of the northern Syrian city of Aleppo on May 20, 2015.

Zein Al-Rifai/AFP

A Syrian man carries a body after it was removed from the rubble of buildings following a barrel bomb attack by government forces on the Qadi Askar district of the northern Syrian city of Aleppo on Wednesday

Tourists enjoy visiting Red Square in Moscow on May 20, 2015.

Kirill Kudryavtsev/AFP

Tourists enjoy visiting Red Square in Moscow on Wednesday

A pickup truck moves off after loading unemployed builders and painters from South Africa and Zimbabwe from a roadside for work in Cape Town, South Africa on Wednesday

Nic Bothma/EPA

A pickup truck moves off after loading unemployed builders and painters from South Africa and Zimbabwe from a roadside for work in Cape Town, South Africa on Wednesday

A Nepalese homeless man sleeps in a street of Kathmandu on Wednesday. Nearly 8,500 people have now been confirmed dead in the disaster, which destroyed more than half a million homes and left huge numbers of people without shelter with just weeks to go until the monsoon rains.

Ishara S.Kodikara/AFP

A Nepalese homeless man sleeps in a street of Kathmandu on Wednesday. Nearly 8,500 people have now been confirmed dead in the disaster, which destroyed more than half a million homes and left huge numbers of people without shelter with just weeks to go until the monsoon rains

A man walks past a billboard at the Global Gaming Expo Asia in the world's biggest gambling hub of Macau on May 20, 2015. The three-day fair of gambling innovations, the largest gaming event in Asia, showcases the industry's latest products, services and technologies at the glitzy Venetian Macau hotel

Philippe Lopez/AFP

A man walks past a billboard at the Global Gaming Expo Asia in the world’s biggest gambling hub of Macau on Wednesday. The three-day fair of gambling innovations, the largest gaming event in Asia, showcases the industry’s latest products, services and technologies at the glitzy Venetian Macau hotel