github : dovecot 2.4 setup for debugging config with docker

[Rory Campbell-Lange <rory@campbell-lange.net>]

A number of people on the dovecot mailing list are writing in due to problems resulting from the configuration changes in the 2.4 series dovecot mail server included with trixie. 

These changes are noted on the trixie release notes here:
https://www.debian.org/releases/trixie/release-notes/issues.en.html#dovecot-configuration-changes

I've put up a very simple dovecot configuration file and example users.db file at https://github.com/rorycl/dovecot-config which can be used with the official dovecot docker image to debug issues, in case it is helpful to anyone.

If you'd like to add a configuration scenario to the repo, please submit a PR in a self-contained directory with a suitable name, with:

* a README.md
* a minimal dovecot.conf
* support files only if needed
* a log file showing the expected output

Thanks!
Rory

p.s. I'm only subscribed to the digest version of this list.