Support re-scanning files from disk

[JonnyOThan]

I've added support for re-loading the profile from the ConfigNode. But it would be nice if TUFX could load profiles from previously unknown cfg files (i.e. you install a profile while the game was already running) as well as re-loading the ConfigNode from the cfg file.

This isn't as easy as it sounds - a tufx profile could exist in any folder, so it would need to load every cfg file from the gamedata folder to look for new ones. It might be reasonable to restrict the search to TUFX/Profiles, but there are TUFX profiles available on CKAN that don't install to that location.