detect the ubuntu version based on /etc/os-release

Uwe Merbeth

2016-05-09 f5daecadf5846ff0b2d512e6a1a47f17342fe02b

 interface/lib/classes/remote.d/mail.inc.php

@@ -357,7 +357,7 @@
         return false;
      }
   
      if (/*$action_type != 'backup_download_mail' and*/ $action_type != 'backup_restore_mail') {
      if (/*$action_type != 'backup_download_mail' and*/ $action_type != 'backup_restore_mail' and $action_type != 'backup_delete_mail') {
         $this->server->fault('invalid_action', "Invalid action_type $action_type");
         return false;
      }