Directed by Cheryl Furjanic. With David Boudia, Jimmy Carter, Sergei Chalibashvili, Mary Ellen Clark. Feature-length documentary about the greatest diver of all time. Four-time Olympic champion Greg Louganis has faced more than his share of challenges. In 2011, he is far from the public eye and struggling to pay his mortgage. Now, the openly gay, HIV+ world-class athlete returns to diving to mentor the USA Olympic hopefuls. This may be his best chance to regain the notoriety -- and financial…