Live music has been putting the dance in Sundance. Dave Grohl kicked off the film festival by playing with his ex-Nirvana bandmates, plus John Fogerty, Stevie Nicks and Rick Springfield for his doc “Sound City,” and rockers have continued to get nearly as much attention as the films. Mark Foster, of Foster the People, DJ’d at the Everest Mansion Saturday night before band Capital Cities took the stage, and actors Paul Rudd and Emile Hirsch were spotted grooving in the crowd. Other VIPS at the Corzo tequila-fueled bash included Alessandra Ambrosio and Tony Danza.