[Feature Request] DLC/CDLC Support

Hi!

Just requesting if possible if nimble can implement support for DLC/CDLC loading? I imagine allowing a field for custom launch parameters would solve this as well, as at the moment it requires grabbing the steam:// launch output and editing the unicode to drop in the CDLC "mod" folder.

Appreciate your development of this one, has made using Swifty on Linux easy!

