* reroute several error conditions to I_Error.
* removed some soon-to-be obsolete GRP loading code.
* explicitly trigger the SetDefaults script events which depended on side effects from the config implementation.
* removed the nonsensical file system switch. All this does is create instabilities because it is non-obvious from where data is loaded. If a resource is mounted, it should be checked for content no matter what. While this may affect the stray weird mod out there it is a necessity if we want to allow transparent project repackaging.
