Changed cron_daily.php to avoid some php notices.

- Implemented FS#3308 - PATH placeholder in directive snippets (placeholder is named {DOCROOT}, like for nginx).

fixed zip-backup and restore, fixed log-output for restore mail-backups, mount backup-dir and try to create the maildir

the path for the dkim-keys is automaticly creaed by the server-plugin, the path could be empty in the interface, and the amavis-template for gentoo was updated

Changed mode of web folder from 0710 to 0711 to make it comaptibe with servers that use NFS for /var/www.

Changed: apps vhost is now a template (for apache version)
Changed: template if tags can now be of format 'version' to make version comparisons (e.g. 2.12 > 2.2 !)
Changed: New apache 2.4 syntax for deny from all (-> Require all denied) etc.