It used to be that if you were a playwright and you wanted to publish the script of your play, you had to go with one of two very old firms — Samuel French or Dramatists Play Service. But now all of that’s changed, thanks to a new company called Playscripts. Kurt Andersen talks with Douglas Rand and Jonathan Rand, the two brothers who started the company when they were students, about how they’re bringing the business of theater into the 21st century.