WIP: Enable rawlogs

[link2xt]

This is what I "delpoyed" manually on nine.testrun.org to enable rawlogs. The result of this is that dovecot starts writing into /home/vmail/mail/[email protected] files with *.in and .*out extensions that have IMAP logs with timestamps.

I needed it to debug IMAP bug that results in CI timeouts. It will be "disabled" by redeploying from the main branch.

Would be nice to turn this into an option so it can be enabled/disabled as needed and at least merge changes fixing the homedir for users, but for now I just want to document what I did because enabling rawlog is not well-documented and other admins have troubles enabling them too.