Add "Personal" as Indexer

[martysmarty]

Currently, only shows that are available on one of the databases, can be added. However, I'm collecting shows from a lot of different languages, and have not yet added all shows the TheTVDB yet.

I would love an option to add a show, without it being TheTVDB/TVMaze/etc. This could be called "Personal" indexer. Post-Processing should still work, as it searches on the name, and can decode the season and episode number directly from the filename