ST. LOUIS (Reuters) - A Missouri judge on Friday ruled a white former St. Louis police officer was not guilty of murder in the 2011 shooting of a black man, sending hundreds of protesters to the city's streets to voice their anger. With the National Guard on standby in case of violence, authorities appealed to protesters to march peacefully in a state that has seen racially charged clashes in the past. Jason Stockley, 36, was acquitted of first-degree murder for killing Anthony Lamar Smith, 24. The former policeman, who was arrested in May 2016, was accused of planting a gun...