Doomsday Engine

Fixed: "External resource loader - File names with extensions" (see here http://sourceforge.net/tracker/index.php?func=detail&aid=2536942&group_id=74815&atid=542099).

• Merged model search path handling into the resource locator.
• A filehash is now built for each resource class.
• Revised resource locator design to shift more work to the file hash creation stage (resource class data, search path variations gamemode, override paths etc).
• Deferred R_InitModels until after the game's post init routine has been called. This allows the game chance to determine the gamemode before we make any attempt at building file hashes so the engine only has to do the later once.
• Numerous routines taking/returning character array ptrs given const specifiers where appropriate.