FERGUSON, Mo. — A Missouri teenager fatally shot by police suffered a bullet wound to his right arm that may indicate his hands were up or his back was turned to the shooter, but “we don’t know,” a pathologist hired by the teen’s family said today. An independent autopsy determined that 18-year-old Michael Brown was shot at least six times, including twice in the head, according to the family’s attorneys and hired pathologists. Brown was unarmed when he was shot by a police …