... and make user experience with skins2 less frightening !

missing files in skins should never occur, but reality is quite different
(see vlc skins website). Yet, if a check is done before any other processing,
we can avoid the unfriendly error dialog boxes issued by vlc core, and those
skins often end up quite usable (missing files are either no longer used or
for ancillary functionalities, that go unnoticed)