The nudity may surprise you. The masturbation scene could distract you. The casting might throw you. Actually, it probably won’t. If you’re going to check out the “all- male, yet not necessarily gay” intepretation of Les Liaisons Dangereuses now being staged by the Actors’ Theatre of Washington, you probably know you’re in for something a little edgy. You’re also in for good, gutsy, even groundbreaking theater. Liaisons manages to question your assumptions about gender…