Fix to Admin Dashboard

Without this change, you can receive the log

[24-Sep-2013 00:04:54 UTC] PHP Fatal error: require(): Failed opening required '' (include_path='.:/usr/share/pear:/usr/share/php') in /var/www/html/demo_160/my_admin/includes/template/partials/tplDashboardMainSortables.php on line 27