OnArray: toString() handle recursive arrays

extension/qfq/qfq/helper/OnArray.php

@@ -33,6 +33,10 @@ class OnArray {
         $dataString = '';
 
         foreach ($dataArray as $key => $value) {
+            if(is_array($value)) {
+                $value = self::toString($value);
+            }
+
             $dataString .= $key . $keyValueGlue . $encloseValue . $value . $encloseValue . $rowGlue;
         }