Package alterator-postfix-dovecot: Information

- hook-net-domain: Fix regexp.
- hook-net-domain: Silence grep output.
- Don't use 'vmail' user for root mail delivery.

- Requre ALT domain for work.
- Don't initialize configuration without domain (closes: #29349).
- Use alterator-service-functions.
- final version 0.6 (by Andrey Kolotov).
- drop installer-feature-mail-init-stage3 (by Andrey Kolotov).

- works with Dovecot 2.x.x through alterator.conf
- remove option smtpd_tls_auth_only, default yes
- SMTP on/off through control postfix server/local
- added SMTP submission on/off through control postfix-submission
- added requires for auth users through dovecot-ldap
- autocreate new user vmail