Most people unacquainted with pro surfer Bethany Hamilton (myself included) may only know about her dangerous run-in with a tiger shark, which resulted in her left arm being bitten off (a story adapted in 2011’s Soul Surfer, based on Hamilton’s autobiographical best-seller).  I wholeheartedly recommend Bethany Hamilton: Unstoppable to those movie goers.  Not only does Aaron Lieber’s documentary fill us in on Hamilton’s career using stylistic flare, but the film does an exceptional job showcasing…