This morning around 6:15 a.m., two people were shot outside the Manhattanville Houses at 1430 Amsterdam Avenue before the gunman shot himself. Now it turns out the shooter was a postal carrier who had gotten into a fight with the men. NY1 reports that 48-year-old Roberto Caballero "had a confrontation with two men," and shot one man three times in the chest and the other once in the head. Then Caballero went to his apartment......