automx2 v2019.0

[Ralph Seichter]

* Wolfgang Rosenauer:

> I'm still not sure how to represent the possibility to offer IMAP via
> STARTTLS and TLS with one of it preferred.

Why would one of those mechanisms be preferred, given that they achieve
the same goal, albeit with a small amount of extra data sent in the case
of STARTTLS? Define both, have the client pick one.

I am aware that the order of entries in the result can indicate order of
preference, but currently the returned server records depend wholly on
the database backend and/or driver, and clients are not guaranteed to
honor order of preference anyway.

-Ralph