code: public static void show(String module, String topic, String label) {
          getViewer(true).show(module, topic, label);
      }
docs: Show help for the given module and optional topic.
  
  @param module The id of the help module.
  @param topic The id of the desired topic. If null, the home topic is shown.
  @param label The label to display for the topic. If null, the topic id is displayed as the
  label.