public function createFolder($name, $title, array $children, $headScript = '')
 {
     if (empty($name)) {
         throw new \Exception('Folder name must be set');
     }
     if (empty($title)) {
         $title = $name;
     }
     $page = new PageBuilder();
     $page->setName($name);
     $page->setTitle($title);
     $page->setTemplateType('default');
     $page->setIsFolder(true);
     $page->setHeadScript($headScript);
     $page->setChildPages($children);
     $this->pages[$name] = $page;
     return $page;
 }