The female prison employee at the center of an investigation into the escape of two killers pleaded not guilty Friday night to helping them flee the maximum security facility. Prison tailor shop instructor Joyce Mitchell, 51, was arraigned on a felony charge of promoting prison contraband and misdemeanor count of criminal facilitation, authorities said. Mitchell is accused of aiding in the escape of inmates David Sweat and Richard Matt from the Clinton Correctional Facility in upstate New York last week. She entered the court room with her hands cuffed in front of her, clad jeans and a lime green top...