In the seventies Ron and Russell Mael fast attracted a fan base thanks to their decidedly unorthodox musical act, the Sparks. Despite changing demographics, shifting musical tastes and their unending oddity, the brothers have managed to enthrall fans well into the 21st century. Director Edgar Wright (“Shaun of the Dead,” “Baby Driver”) is just one among those many famous fans to wax nostalgic about the band, with a new documentary