[Implemented] Custom title for TV episode extras

Since the show name and episode title are basically irrelevant (the scanner only looks for S1E1 or 1x01), I’d like to suggest this:

TV Show (Year)/
└─ Season 1/
   ├─ TV Show - S1E1 - Episode Name.ext
   ├─ TV Show - S1E1 - Extra Name-behindthescenes.ext
   ├─ 1x02 Episode Name.ext
   └─ 1x02 Extra Name-behindthescenes.ext