Masterpiece's Little Women marks a breakthrough for PBS: It’s produced by BBC, which, producer Rebecca Eaton noted, "does not do American drama.” “It's hard to get America novels done with BBC because they are BBC – they have a mandate,” she said. Additionally, it can be expensive. “If you shoot in this country, it’s twice as expensive.” Set in Concord, MA, Little Women was filmed in Ireland. It helped that Colin Callender was “the guy who was going to drive the train”…