The violent vagrant arrested for attacking a 20-year-old NYU coed in an unprovoked attack Monday morning has a troubling history of cowardly assaults on women, The Post has learned. James Rizzo, a 45-year-old homeless brute with 16 prior busts, including for sexual abuse and forcible touching — and even a 1997 murder rap — was charged Tuesday evening with shoving college student Amelia Lewis to the ground as she walked to class in Lower Manhattan on Monday morning.