Configuration files go to this directory.

The configuration files that are provided here should work out of the box on
Slackware once you've installed security certificates to support SSL/TLS.

See the config file beneath this directory:  conf.d/10-ssl.conf

For a script that will install self-signed certificates, see mkcert.sh in
/usr/doc/dovecot-2.*

It is also recommended to edit conf.d/10-auth.conf and uncomment this line:
#disable_plaintext_auth = yes

This will prevent usernames and passwords from being sent until a secure
connection has been established.
