configure_amavis() adds some extra lines to postfix's main.cf & master.cf
which are not required and are leading to malfunction when amavis is not installed.

- Add config to clear php handler in apps vhost.

- Added options to use a mounted backup directory. This allows for remote backups, e.g. vis sshfs to a backup server. The backup script checks if the backup directory is mounted, and if not, tries to mount it.

Fixed login as

- Added fields to client, reseller and website to show when a record was added and by which user

skip writing dkim-values for inactive domains
removed the public-dkim-key from the interface
added german language-file