Previously we only supported a single 'required tag group' for a category. This commit allows admins to specify multiple required tag groups, each with their own minimum tag count.
A new category_required_tag_groups database table replaces the existing columns on the categories table. Data is automatically migrated.
* FEATURE: add category banner for why a user cannot post
Adds a category banner for why a user is unable to post in a category.
Also adds an extra alert for the user when a user is unable to create a topic in a
category and they still try and click on the disabled-looking new topic
button.
In a category's settings, the Tags tab has two new fields to
specify the number of tags that must be added to a topic
from a tag group. When creating a new topic, an error will be
shown to the user if the requirement isn't met.
