Armed with a limitless Rolodex and a Benedict Canyon enclave with its own disco, Allan Carr threw the Hollywood parties that defined the 1970s. A producer, manager, and marketing genius, Carr built his bombastic reputation amid a series of successes, including the mega hit musical film “Grease” and the Broadway sensation “La Cage Aux Folles,” until it all came crashing down after he produced the notorious debacle of the 1989 Academy Awards.