Graphics setting changes.

Makes the overlay settings more clear by indicating that the settings are for Blish HUD (some users would mistake the graphics settings as somehow applying to the game).
Remove the option to toggle vsync (it is now always off unless framerate is set to Unlimited).
Added new hidden frame limiter setting which is enabled using the old --unlockfps launch arg which truly unlocks the FPS (intended for things like module development).

As part of migrating to this version, the previous vsync settings are ignored and unlimited has been migrated to Match Monitor Refresh Rate).

blish-hud / Blish-HUD