Improve offboarding
As mentioned here, the offboarding doesn't work yet.
- homdir on gemini is not deleted
- user on mail is not removed
- user still can login to imap
- homedir on mail is not removed
- if the user used the IMAP server, there is still a mailbox
- it's unclear what to do with the existing data and mailbox (delete? forward?)
Edited by Frederik Schwan