Stephen Ames chuckled about his mostly mediocre 18 holes of golf. He can laugh all the way to the bank. With $650,000 at stake on No. 18, Ames coolly knocked his 7-foot birdie putt into the center of the cup Sunday to win the Skins Game. The only other hole he won was the first, a day earlier. “That’s the nature of the Skins Game,” Ames said, his smile still as wide at it was when his rich putt…