Steam has a new feature in beta aimed at helping completionists feel like they’ve got a bit more of a handle on their never-ending quests to 100% games whose trophy lists keep on growing and evolving. Steam achievements can now be grouped into sets determined by the developers, creating a means of separating off the likes of DLC trophies from the base game’s to-do list, thereby making it clearer what you’ve done so far and where you might want to…