An attempt to fix #57 (Warzone 2100 doing an emergency shutdown due to music still playing when changing mounted mods)
Now moved to #70 (Implement safe mod switching)

Affects trunk/src/init.c#L161, trunk/src/main.c#L394 and surrounding areas.

Old behaviour

(rough lineout, just looks simpler than the proposed process)

• Start Warzone 2100
  • Try to mount /base in all datadirs
• Start a game
  • Figure out whether we want to start a mp or campaign game
  • Find out which mods are necessary for that
  • Clean the search path
  • Mount the appropriate new files
• Close a game
  • Clean the search path
  • Mount /base again

Proposed new behaviour

• Start Warzone 2100
  • Try to mount /base in all datadirs
  • Mount all mods requested (no more mp/cam only mods -- simplification, may be postponed)
• Start a game
  • Shutdown Warzone 2100
  • Unmount everything
  • Mount /base
  • Mount /mp
  • Mount all mods requested (no more mp/cam only mods -- simplification, may be postponed)
  • Restart Warzone 2100 to catch up all changed files (music, etc)
• Close a game
  • Shutdown Warzone 2100
  • Unmount everything
  • Mount /base
  • Mount all mods requested (no more mp/cam only mods -- simplification, may be postponed)
  • Restart Warzone 2100

The idea behind this is, that a shutdown and restart ensures that no files are still opened, and thus we can mount / unmount without any problems.