In todays’ roundup, Mark Hamill, Lena Headey, and David Bradley join the cast of “Trollhunters,” and “AMC Visionaries: Robert Kirkman’s Secret History of Comics” gets a premier date. CASTING Mark Hamill, Lena Headey, and David Bradley have been cast in Season 2 of Guillermo del Toro‘s animated Netflix series “Trollhunters.” Hamill will play an evil...