- add managemails.apps to give a more meaningful title in the admin site
- add verbose names to MailAddressMailbox fields
- implement managemails.models.Mailbox.get_mailaddresses and a corresponding
property mailaddresses
- add migration to place a unique constraint on MailAddressMailbox.mailaddress
and drop existing primary_key
- change managemails.models.MailAddressMailbox.mailaddress to OneToOneField