HaikuDepot: Filter ratings by preferred languages

Show only those user ratings which are in one of the
languages configured in the Locale preflet's preferred
languages list.
Media Preflet: fix #11308
_ClearParamView() should not remove fMidiView, since it's not dynamically
generated.
Media Preflet: Use BPathFinder::FindPaths() instead of the C method.
This way we can use BStringList and get rid of the manual deallocation.