The expansiveness of Questlove’s contact list is in full evidence in his new documentary chronicling the lengthy career of the legendary band Earth, Wind & Fire. Besides the many past and present band members on display, the film includes commentary by such figures as Stevie Wonder , Lionel Richie , H.E.R. and Flea , among others, all attesting to the band’s lasting influence. Oh, and there’s also Barack and Michelle Obama, commenting on such weighty issues as the intricacies of slow dancing to the band’s love songs. The musician/filmmaker — who has demonstrated his cinematic bona fides with his Oscar-winning Summer of Soul and Sly Lives! — delivers another superb effort with the colorfully titled Earth, Wind & Fire (To Be Celestial vs. That’s the Weight of the World ), receiving its world premiere as the opening night film of the Tribeca Film Festival days before airing on HBO.  Earth, Wind & Fire (To Be Celestial vs.…