By CLIFF BRUNT, AP Sports WriterNBA MVP Kevin Durant has added action sports accessory brand Neff to his rapidly growing list of endorsement deals. Neff founder Shaun Neff told The Associated Press that the company will launch the Thunder star’s signature underwear collection in time for next year’s back-to-school crowd. Neff, which has continued to expand beyond snow and skate headwear, does not currently have an underwear line.Read more on NewsOK.com