Merge branch 'ftp_statistics' into 'stable-3.1'

missing menu for ftp stats

Hi, 

I forgot to send /interface/web/sites/lib/module.conf.php.
Now the ftp stat can be accessible by interface


See merge request !280

interface/web/sites/lib/module.conf.php

@@ -194,6 +194,11 @@ $items[] = array(   'title'   => 'Web traffic',
 	'link'    => 'sites/web_sites_stats.php',
 	'html_id' => 'websites_stats');
 
+$items[] = array(   'title'   => 'FTP traffic',
+	'target'  => 'content',
+	'link'    => 'sites/ftp_sites_stats.php',
+	'html_id' => 'ftpsites_stats');
+
 $items[] = array(   'title'   => 'Website quota (Harddisk)',
 	'target'  => 'content',
 	'link'    => 'sites/user_quota_stats.php',