Deleting team email addresses

I think the next bug for me to work on after hours is bug #250103 [Teams cannot delete old email addresses]

This causes users and myself a lot of problems. While you can change a team email address in Launchpad, it never deletes the old one. It is kept and it is hidden so that it can never be reused. This is very annoying because users, not team own the address, so the user can never reclaim his address once he gives it to a team. This leads to a lot of requests to delete the address via SQL. This also prevents me from removing teams or their artefacts in my role as a Registry Administrator.

The right behaviour is to delete the email address when it is deactivated for the team. This is what the UI implies happens. Users can re-register the address when they choose to use it again.