feature #392, add authentication key in NBM mails

There are many links in NBM (Notification By Mail, see screen
[Administration > Users > Notification]). I had to change several
functions to take this authentication key into account.

admin/include/functions_notification_by_mail.inc.php

@@ -125,12 +125,12 @@ select
   U.'.$conf['user_fields']['username'].' as username,
   U.'.$conf['user_fields']['email'].' as mail_address,
   N.enabled,
-  N.last_send
-from
-  '.USER_MAIL_NOTIFICATION_TABLE.' as N,
-  '.USERS_TABLE.' as U
-where
-  N.user_id =  U.'.$conf['user_fields']['id'];
+  N.last_send,
+  UI.status
+from '.USER_MAIL_NOTIFICATION_TABLE.' as N
+  JOIN '.USERS_TABLE.' as U on N.user_id =  U.'.$conf['user_fields']['id'].'
+  JOIN '.USER_INFOS_TABLE.' as UI on UI.user_id = N.user_id
+where 1=1';
 
     if ($action == 'send')
     {
@@ -159,7 +159,7 @@ order by';
     else
     {
       $query .= '
-  username;';
+  username';
     }
 
     $query .= ';';