(Reuters) Armed robbers posing as police officers held a gun to the forehead of U.S. gold medalist swimmer Ryan Lochte in a taxi hold-up in Rio de Janeiro on Sunday, feeding concern over safety at the first Olympic Games in South America. Lochte was returning to the Athletes’ Village from a party hosted by the French Games delegation, with swimming team mates Gunnar Bentz, Jack Conger and Jimmy Feigen, when armed men carrying police […]