Coop merge

These changes allow coop maps to show up in the normal map selector, and allow the game to launch with only one player if it detects a coop map. The game launches. However, this approach is basically making the bare minimum of changes needed (The coop system as-is is incredibly out of date). There WILL be bugs, but only when playing through coop maps. The best way to fix them IMO is to play through with logging open and fix the bugs and errors as they appear.