Bitwig has a built in device that can do any 12-note tuning or equal division of the octave tuning (with tweakable octave I think). That said it cannot really do other tunings. But these two types of tuning are the most common, and I guess with the new Note Grid device it should in theory be possible to do pretty much any tuning.
Edit: it looks like sevish has multiple notes tuned the same in order to get less than 12 notes per octave, so that's also possible.
I've been a bit frustrated with the inability to work easily in Ableton 9 with non-Western or microntonal tunings.