Payton Gendron, 18, of Conklin, NY, pleaded not guilty to first-degree murder. Police say the rambling text of a 180-page manifesto that Payton Gendron posted included a plan of the attack which detailed driving several counties away to carry out the rampage the Tops Friendly Market WHAT WE KNOW ABOUT THE VICTIMS KILLED IN BUFFALO SUPERMARKET SHOOTING Aaron Salter, 75, …