initiate variable

page-logic/validator.php

@@ -2,6 +2,7 @@
 require_once ("../lib/validatorClass.php");
 session_start();
 $v = new Validator();
+$data = '';
 if ($v->params['url'] && $v->params['auto'] && $v->params['xmlout']) {
     header('Content-Type: text/xml');
     list($schres, $printres) = $v->checkmetadata();