Fix sorting order
    
    * Split on / separator before sorting, so we don't sort
        org.freedesktop.Platform.GL.default/*
      before
        org.freedesktop.Platform/*
    
    * Don't sort items with the same download count in *reverse* alphabetical order.
    
    * Sort filters by our "short IDS", using the same sorting logic as otherwise.
      This avoids having runtime/... between org.. and us...