Feature Request: Genre Mapper to Blank (ie: Remove specific Genre)

[undaunt]

Is your feature request related to a problem? Please describe.
I have a subset of films that have extra genres that I cannot easily remove without statically updating the metadata on a per movie basis.

Describe the solution you'd like
I'd like to be able to map them away, similar to how I do this with existing genres. IE: I have 50 films that are Thriller, and 1 that is suspense, so I map Suspense to Thriller. But I have 19 films that are 'TV Movie', and I simply want to map that to nothing and delete it without having to iterate out all 19 in a metadata file.

Describe alternatives you've considered
I've considered the genre updater to IMDB or TMDB genre's, but the New Plex Movie agent seems to have a different set of genre's from both of those sources which I would like to, on the whole, maintain, except for in these key corner scenarios.

Additional context
If there is a way to combine IMDB or TMDB genre updater with the genre mapper, this may also let me solve the problem, but it seems like an either/or right now.

Thanks!