Medium-grade Allen film anchored by a mysticAmong recent Woody Allen films, the crabby but pretty "Magic in the Moonlight" is a well-thumbed playing card from the middle of the deck, not one of his fully good ones ("Midnight in Paris," "Vicky Cristina Barcelona"), not one of the whiffs ("Cassandra's Dream," "Scoop," "You Will Meet a Tall Dark Stranger").