Tim Robbins and Mark Ruffalo have joined the cast of Gilbert Films and Class 5 Films' independent comedy "Thanks for Sharing."According to Variety, the film marks the directorial debut of Stuart Blumberg, who was nominated for an Oscar for co-writing "The Kids Are All Right."Blumberg co-wrote the 'Sharing' screenplay with Matt Winston.Gary Gilbert and Jordan Horowitz are producing for Gilbert Films, with William Migliore and David Koplan producing for Class 5.The story focuses on a group of men developing friendships while in a 12-step program for recovering sex addicts.Production begins in New York this fall.Ruffalo is currently shooting the Marvel superhero tentpole "The Avengers." Robbins will be seen in Warner's upcoming superhero film "The Green Lantern."...