Steve Martin and Martin Short’s “You Won’t Believe What They Look Like Today!” is a show that redefines the form in unexpected and profound ways, from two of the funniest, most influential and acclaimed talents of the past century. Their humor is often subversive, but it is always a joyous self-deprecating romp from two comedy masters driven to make each other laugh as much as the audience. The jokes come at you at a rapid-fire pace with little set-up and…...