/**
 * Display page title
 *
 * Parameters:
 * 
 * - default - default page title, if no page title is present. If there is no 
 *   default value 'Index' is used
 * 
 * @param array $params
 * @param Smarty $smarty
 * @return string
 */
function smarty_function_page_title($params, &$smarty)
{
    $default = array_var($params, 'default', 'Index');
    $page_title = PageConstruction::getPageTitle();
    return empty($page_title) ? clean($default) : clean($page_title);
}