This year's 2012 Cannes Film Festival will showcase films from "Twilight" power couple Robert Pattinson and Kristen Stewart. Both "On the Road" and "Cosmopolis" will premiere at the prestigious event, allowing the actors to distance themselves from their vampire alter-egos. Both Stewart and Pattinson (aka Robsten) are starring in a number of intriguing new projects from big budget blockbusters…