The most important reason for the release was a SECURITY FIX: don't allow to
delete protected aliases (CVE-2017-5930, PR#23). Thanks to Janfred @github for
the report and the pull request!
Besides that, the following non-security bugs were fixed:
- fix VacationHandler for PostgreSQL
- AliasHandler: restrict mailbox subquery to allowed and specified domains to improve performance on setups with lots of mailboxes
- allow switching between dovecot: password schemes while still accepting passwords hashed using the previous dovecot: scheme
- FetchmailHandler: use a valid date as default for 'date'
- fix date formatting in non-english languages when using PostgreSQL
- various small fixes