DVD: Show the "nature|type" of a track
As in: visually impaired, director's comments, alternate director's comments etc. A track name in the menu would then show: Track 1 - [language] Nature
DVDs support this trough the "code extension" of the track attributes. See also: http://dvd.sourceforge.net/dvdinfo/ifo.html#spatt
We need yet another extension for dvdnav to support this. We need to retrieve the code and match that code against a table with the (translatable) full name of the extension. (Native support in our spu_track_t should be implemented)