A Monmouth County man who admitted last year that he intentionally killed his cat while recording the act and taking photos of the dead animal was sentenced Thursday to four years and six months in state prison, authorities announced Friday. Police began investigating on March 31, 2013 after getting called to a residence for an unrelated matter. Officers found the dead cat outside the Howell home of 29-year-old Christopher Sanchez, the Monmouth County Prosecutor’s Office said. Initially, Sanchez told police that the cat’s death was a mercy killing necessitated by her being mortally injured fro…