* Stuff to do
** PROGRESS Add smtp support (postfix?)
** PROGRESS Add imap support
** PROGRESS Define where/how to save mails
   - /data would be fitting
** PROGRESS Add db support (?) or not?
   - all file based could be very easy
   - restarts are usually fine
   - requires dovecot in same containerx
** TODO Define deployment requirements (such as SPF/DKIM etc)
** TODO add stdout logging

 Logging to stdout is useful when Postfix runs in a container, as it eliminates a syslogd dependency.

    Add the following line to master.cf if not already present (note: there must be no whitespace at the start of the line):

        postlog   unix-dgram n  -       n       -       1       postlogd

    Note: the service type "unix-dgram" was introduced with Postfix 3.4. Remove the above line before backing out to an older Postfix version.

    Configure main.cf with "maillog_file = /dev/stdout".

    Start Postfix with "postfix start-fg".
** TODO Check EAI support
   - https://en.m.wikipedia.org/wiki/International_email
   - https://www.icann.org/get-ua-ready-en