Merge branch '1-error-if-no-element-t3js-banners' into 'master'

Resolve "Error if no "element" // ".t3js-banners""

Closes #1

See merge request t3o/randombanners!2

Resources/Public/Javascript/randombanners.js

@@ -7,8 +7,10 @@ var randombanners = {} || window.randombanners;
  */
 randombanners.shuffle = function (element) {
     $element = document.querySelector(element);
-    for (var i = $element.children.length; i >= 0; i--) {
-        $element.appendChild($element.children[Math.random() * i | 0]);
+    if ($($element).length > 0) {
+        for (var i = $element.children.length; i >= 0; i--) {
+            $element.appendChild($element.children[Math.random() * i | 0]);
+        }
     }
 };