A 17-year-old boy was arrested and accused of murder in the stabbing death of a 15-year-old boy at a crowded house party on Long Island, authorities say. The Syosset High School student, who prosecutors described as an accomplished wrestler and trained in martial arts, faces 25 years to life in prison if convicted. Prosecutors say that on Nov. 3, the defendant and two other friends from Syosset went to a house party in West Babylon on Carlton Road, despite not being invited. When they arrived to