Non-spoiler alert: the title character never appears in David Rabe's "Good for Otto", making its New York premiere onstage at the Alice Griffin Jewel Box Theatre at the Pershing Square Signature Center.  Unlike Harvey the rabbit, the beloved pet hamster really exists.  His well-being is one of several crises in Rabe's passionate exploration of mental health providers and patients.  Like the subject matter, there are no easy solutions.  Such long-term perimeters limit the play's message that even its accomplished cast cannot answer in three hours. Rabe returns to his familiar theme of the extended family created by circumstance. Drs. Michaels (Ed