CLEVELAND, April 15,2009(AP) Stumbling as the final seconds ticked off in a regular season that was anything but ordinary, Cavaliers guard Daniel Gibson got a look at the rim about 30 feet away. He then fell to the floor. Cleveland’s last shot at history dropped with him. Gibson, whose 3-pointer in the last second of regulation forced overtime, fumbled away Cleveland’s last possession as the Cavaliers, who sat superstar LeBron James and other regulars to rest for the playoffs, lost for just …