At Sundance, directors Betsy West and Julie Cohen shine a bright light on the life (personal and political) of the so-called Notorious RBG. Ruth Bader Ginsburg’s life — and its many lessons, both learned and taught — come to entertaining and energetic life. It’s a fist-pumping, crowd-pleasing documentary that makes one heck of a play to remind people of Ginsburg’s vitality and importance, now more than ever.