Add actions for add_role() and remove_role()

[danielbachhuber]

set_user_role() has an action which is nice for audit purposes. It would be great if add_role() and remove_role() had similar actions to make sure there aren't any leaky spots in the audit log.

[shooper]

Thanks for submitting this Daniel. It's something that was bothering me too. I've created the patch for it.

[DrewAPicture]

32060.2.diff​ adjusts the hook docs syntax and adds @since versions for 4.3.

[nacin]

All hooks in WordPress with the word "added" or "deleted" use it as a prefix, not a suffix. Verb + noun is pretty common for us. I'm going to change this to added_user_role and removed_user_role.

[nacin]

Consistency!

• I was going to change $this->id to $this, but set_user_role uses $this->id.

• I was going to change these to added_user_role and removed_user_role, but to match set_user_role, I'm going to go with add_user_role and remove_user_role instead.

[nacin]

In 32771:

Add add_user_role and remove_user_role actions for WP_User::add_role() and remove_role().

props shooper.
fixes #32060.