“Last week, in front of hundreds of group-sales executives, Disney unveiled plans for a $10 million (at least) stage version of its animated movie “Tarzan” that will open at the Richard Rodgers Theatre in May. Usually at these events, the sales people are treated to a few musical numbers, and, if you sneak into the theater, you can get a pretty good idea of whether the show’s going to be a stinker or a hit. But “Tarzan” isn’t even in rehearsal yet, so Tom Schumacher, the popular head of Disney’s theater division, hosted what amounted to an informal chat show that might have been called Tom and Friends.”