Implemented FS#2382 - automatically add alias domain when creating a domain

interface/web/admin/form/server_config.tform.php

interface/web/admin/lib/lang/de_server_config.lng

interface/web/admin/lib/lang/en_server_config.lng

interface/web/admin/templates/server_config_web_edit.htm

server/plugins-available/apache2_plugin.inc.php

server/plugins-available/nginx_plugin.inc.php