NEW: module_system | class_carrier -> added a centralized method  public function flushCache($intCacheType = 0). single point to flush the systems various temporary caches
BUG: module_system | class_rights -> fixed a race condition where changing a modules permission could lead to inconsistent permissions of child nodes (due to cached module nodes)
NEW: module_system | class_rights -> when changing permissions recusively, the re-write is skipped for nodes not inerhiting the parent nodes' permissions