Workaholics isn’t the most sophisticated comedy out there. But few shows are able to relish in their immaturity with the commitment and crazy-eyed delight Workaholics seems to traffic in. It’s raunchy and sometimes dumb and often tasteless, but it’s joyously those things. Often the show’s sensibility expresses itself as what hyperpolite church ladies might call “toilet humor,†but on last night’s season premiere, the show gave the world a perfect gift: a joke about the best damn book any fourth-grader has ever read. (No offense, The Giver.)