Simplify discussion/tag permission logic
Simplify discussion/tag permission logic

A user now must have a permission to act for *all* tags assigned to a discussion, rather than just one of them. This is consistent with the way the permissions are worked out for visibility.

Luceos/flarum-tags,flarum/flarum-ext-tags,flarum/flarum-ext-tags,Luceos/flarum-tags