Save some memory in parse_directory_sector() by making lfnbuf1 & lfnbuf2 static. Found a bug where long file names can continue over into different sectors. Added static int contin variable to fix. (lfnbuf1 & lfnbuf2 needed to be static for this to work anyway).

Fixed a bug that made the user have to use /sd as a mounting point. They can mount it as anything now.