[Dovecot] Configuration file changes

[Timo Sirainen]

I was going to add support for "configuration groups", but got a bit
stuck at how the logic is supposed to work. I think there could be
different settings based on IP/port it's listening in, or based on given
username.

I can't really describe how it would work, and I'm not entirely sure
myself either :) Does this make sense:

# (default settings here)
# if auth groups are defined here, they are included in all groups below

group 1.server.org {
  protocols = imap imaps pop3 pop3s
  ssl_cert_file = /etc/ssl/certs/server1.pem
  login_dir = /var/run/dovecot/login/server1
  login {
    # common for imap/pop3
    listen = 1.server.org
  }
  auth server1 {
    mechanisms = plain
    userdb = ldap /etc/ldap-server1.conf
    passdb = ldap /etc/ldap-server1.conf
  }

  group admins {
    mail_full_filesystem_access = yes
    auth admins {
      mechanisms = plain
      userdb = passwd-file /etc/admins.passwd
      passdb = passwd-file /etc/admins.passwd
    }
  }
}

# (any setting changes here would affect only new groups below, otherwise
# the config file parsing would get difficult..)

group anonymous {
  protocols = imap
  ssl_disable = yes
  login_dir = /var/run/dovecot/login/anonymous
  login {
    listen = anonymous.server.org
    process_per_connection = no
    processes_count = 1
  }
  auth anonymous {
    mechanisms = plain anonymous
    userdb = passwd-file /etc/anon.passwd
    passdb = passwd-file /etc/anon.passwd
  }
}