I’ll leave the debate over the significance of the 1970s cartoon “Fat Albert and the Cosby Kids” to those who spent their Saturday mornings watching it, but one thing I do know: The series has made for a lousy, live-action movie. With nostalgia as its ace card, this slaps together familiar characters, old catch phrases and lame attempts at irony in the hopes of selling tickets. In other words, the jolly “Hey! Hey! Hey!” of Albert (Kenan Thompson) sounds suspiciously like a carnival barker’s call.