Like all good character actors, Bob Gunton is probably known more by his face than his name – his craggy, often impassive visage has essayed a score of tough, taciturn, often morally questionable men, the best known of which was the cold-hearted warden in “The Shawshank Redemption.” But the California native has given life to a wide variety of roles during his four decades as an actor, including several award-winning musical performances on Broadway and in several comedies, including “Ace Ventura: When Nature Calls” on the big screen and the cult series “Greg the Bunny” (2002) on the small