Talented but troubled Giants wideout Plaxico Burress, adding to his litany of off-field woes, accidentally shot himself in the leg on Friday night, a source told the Daily News on Saturday. Burress, 31, spent the night at a Manhattan hospital with the self-inflicted wound, according to the source. The injury was described only as non-life-threatening, and details of the accident remained sketchy. The Super Bowl hero, who caught the game-winning pass from Eli Manning, was already expected to miss Sunday's game against the Washington Redskins with a hamstring injury. The Giants were due on a Saturday afternoon flight to Washington....