Austin Whitney walked on Saturday. No faith healers were involved. Yet when the paralyzed 22-year-old rose from his wheelchair and stepped across the UC Berkeley commencement stage to shake Chancellor Robert Birgeneau's hand, the crowd of 15,000 at Edwards Stadium went wild with cheers, as if witnessing a miracle. In a way, they were. "Ask anybody in a wheelchair; ask what it would mean to once again stand and shake someone's hand while facing them at eye level," Whitney said in anticipation of his momentous day. "It will be surreal, like a dream." Or like putting on the Iron Man...