Mention ap_state_query() in the new API docs

      <li>New function ap_get_server_name_for_url to support ipv6 literals.</li>

      <li>New function ap_register_errorlog_handler to register errorlog

          format string handlers.</li>

      <li>New function ap_state_query to determine if the server is in the

          initial configuration preflight phase or not. This is both easier to

          use and more correct than the old method of creating a pool userdata

          entry in the process pool.</li>

    </ul>

  </section>