ALICIA POWELL PETS can easily bond with humans, but when a wild octopus befriends a diver and becomes his life coach, that true story scores a best documentary nomination for this Sunday's Oscars. Ten years in the making, "My Octopus Teacher" began as a personal video project by South African filmmaker Craig Foster to rekindle his connection with nature by observing an inquisitive female mollusc while free-diving near Cape Town. She shared with him her secret life in an underwater kelp forest every day for a year before her death after mating and laying eggs, and the pair developed a…