postfix: Stricter configuration
postfix: Stricter configuration

- Relay mail through mail.#!.sh
  This should help not getting our mail classified as SPAM
- Pin the relay's certificate and enforce use of strong crypto
- Refuse incoming mail that does not come from mail.hashbang.sh
- Do not let unprivileged users inspect or flush the mail queue

KellerFuchs/shell-etc,KellerFuchs/shell-etc,hashbang/shell-etc,hashbang/shell-etc,hashbang/shell-etc,hashbang/shell-etc,KellerFuchs/shell-etc,KellerFuchs/shell-etc,hashbang/shell-etc,KellerFuchs/shell-etc,KellerFuchs/shell-etc,hashbang/shell-etc,hashbang/shell-etc,hashbang/shell-etc