By Sam Frost & Sam Frost Nick Dunlap made golf history with his win at The American Express on Sunday and faces a huge decision due to his success. The 20-year-old, a second-year student at the University of Alabama, became the first amateur to win on the PGA Tour since Phil Mickelson in 1991, winning at PGA West in Palm Springs, California by one shot from South Africa’s Christiaan Bezuidenhout. Dunlap’s impressive 12-under-par round of 60 on Saturday put him ahead of the pack, and he managed to fend off a high class chasing group including Ryder Cup stars Justin Thomas, Xander Schauffele and…