ROBBIE ROBERTSON Finding good medicine by fearlessly facing his past Robbie Robertson always avoided addressing touchy subjects like his early days with the Band, his decision to leave the group in 1977, and his wild times during those days with his longtime collaborator, movie director Martin Scorsese. But on How to Become Clairvoyant, his first new album in 13 years, the Toronto-born singer, songwriter, guitarist and film-music composer tackles...