private function addCustomPluginNamespaces(Twig_Loader_Filesystem $loader, $pluginName)
{
$pluginManager = \Piwik\Plugin\Manager::getInstance();
$plugins = $pluginManager->getAllPluginsNames();
foreach ($plugins as $name) {
$path = sprintf("%s/plugins/%s/templates/plugins/%s/", PIWIK_INCLUDE_PATH, $pluginName, $name);
if (is_dir($path)) {
$loader->addPath(PIWIK_INCLUDE_PATH . '/plugins/' . $pluginName . '/templates/plugins/' . $name, $name);
}
}
}