Yoko Ono, George Martin, Paul McCartney and Ringo Starr at the Las Vegas premiere of Love, the subject of the documentary All Together Now. Combining the music of the most beloved band in the world with the most visually arresting live performance troupe working today seems like a surefire recipe for a hit. That’s probably what the late George Harrison and Cirque du Soleil founder Guy Laliberté thought when they first dreamed up the…