Source: New York Times By THE ASSOCIATED PRESS ATHENS, Greece — Just as Europe starts sending would-be migrants back to Turkey, the leaders of the Catholic and Orthodox churches are heading to a Greek island to voice solidarity with those who have streamed in fleeing war, poverty and persecution. Saturday’s high-powered visit to Lesbos by Pope Francis, Ecumenical Patriarch Bartholomew I, the spiritual leader of the world’s Orthodox Christians, and Athens Archbishop Ieronymos, the head of the Church of Greece, could embarrass EU leaders already under fire from human rights groups. The Vatican said Thursday that Francis’ five-hour visit to…