Refactor when Events inherit taxonomy-terms from Productions

[carstingaxion]

While writing my draft of a roadmap comment, I stumbled accros the functionality of automated, in other words: inherited, taxonomy terms for Event-posts coming from their related Production-posts.

This seems (to me) to be a nice candidate for an extension.

1. I would register this as a post_type_support for the wp_theatre_event post_type. This helps capsuling the functionality.
2. Within the rewritten code I would rely on get_post_types_by_support(), which would allow other plugin-authors to add this automatism as well or remove it at all.
3. Next to the built-in taxonomies I could imagine, that it could also be handy for some setups to allow this automated term-creation for custom taxonomies as well.

[slimndap]

Is this about events inheriting the post-category from productions?
I think we should consider using a custom taxonomy for this. The shared use of post-categories between posts, productions and events does not make any sense and is confusing as well.
Making it easy to add multiple cusotm taxonomies sounds great (genre, tags, free/paid, age rating, disability support).