“Nat Turner: Troublesome Property” recalls the 1831 Virginia slave revolt that has become mythical in the years since Turner was hanged. It also looks at how he has been appropriated by both blacks and whites. Filmmaker Charles Burnett does this through comments by experts (some dueling) and handsome re-creations in which different actors play Turner. Confusing? Not at all, because it drives home Burnett's central point, which novelist William Styron puts thusly: “He fits no mold and every mold all at once.”