NEW YORK (Reuters) — U.S. authorities arrested a former president of the United Nations General Assembly on Tuesday for engaging in a wide-ranging corruption scheme involving a billionaire Macau real estate developer and four other defendants.John Ashe, the U.N. ambassador from Antigua and Barbuda who was president in 2013, was accused in a complaint filed in New York of taking more than $500,000 of bribes from Ng Lap Seng, who wanted to build a multibillion-dollar U.N.-sponsored conference center in Macau.In exchange, Ashe told the U.N.