add amavis-configfile-location for centos 6.4; add amavis-initscrip-name for centos 6.4; fixed missing private_key in mail/mail_domain_dkim_create.php

Changed query syntax of alias domain edit file
Changed deprecated syntax in alpha plesk importer

- nginx: added {DOCROOT} and {FASTCGIPASS} placeholders to directive snippets and nginx Directives fields.

display dns-record for dkim in the mail-domain
rewrite function domain_dkim_update in server/plugins-available/mail_plugin_dkim.inc.php
change dns*.php according to commit 604c0c24

- Display server name in all web domains select fields so that you know which domain from which server you select.

add database-size monitoring. the results stored in the database may be used to add the db-size to the web-quota, too.