FenPhoenix
Option overrides
Add per-FM and per-game "option overrides" (pass config vars to the game).
- [x] Add per-FM mantle mode
- [x] Add "use old mantle for all OldDark missions" option
- [x] Add per-game mantle mode
- [ ] Decide if we want to support other stuff like "screenshot mode" or the "d3d_disp_sw_cc" gamma fix thing etc.
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When I used to do videos, I would often find it necessary to change certain options temporarily in various config files ("inv_status_height 0" in user.cfg for hiding the HUD for screenshots, "force_windowed 1" in cam_ext.cfg when I was streaming, etc.). This was always a pain. We should have an option to run the game with a set of custom options and provide some checkboxes and an additional text field for writing in custom commands. Some options can be passed on the command-line; others will need to have their appropriate files temporarily changed. That will require us to track the running of games, rather than just fire-and-forget like we do now.
