[Feature request] Add taxonomy support

Hello,

This plugin is amazing! Though it would be great if we could also limit post creation based on taxonomy. For instance, a user can create three posts per month that have the post type ‘post’ with the taxonomy ‘category’ having the value of ‘press-release’, while being able to create 12 posts per month of custom post type ‘video’ with the custom taxonomy ‘genre’ having the value of ‘media-statement’ … you get the drift.

Also, can it be used to limit media file uploads?