The lines outside the NBA Store snaked around the block in Midtown Monday, as Knicks merchandise has become the Big Apple’s biggest commodity following the teams historic NBA championship. Thousands of diehard fans waited anxiously outside the Fifth Avenue retailer for over an hour for a slim shot at any remaining Knicks gear — still a better bet than ordering team merchandise online, which would mean the deliveries won’t come for at least a month. “The line is an hour and a half,” Brooklyn fan