/**
  * Callback function to change a template handle in each newsletter field.
  *
  * @param string $context
  * @return void
  */
 public function templateSaved($context)
 {
     $old_handle = $context['old_handle'];
     $new_handle = Lang::createHandle($context['config']['name'], 255, '-');
     EmailNewsletterManager::updateTemplateHandle($old_handle, $new_handle);
 }