Document new ping parameter.

        <td>The time to wait for additional input, in milliseconds, before

        flushing the output brigade if 'flushpackets' is 'auto'.

    </td></tr>

    <tr><td>ping</td>

        <td>0</td>

        <td>Ping property told webserver to send a <code>CPING</code>

        request on ajp13 connection before forwarding to it a request.

        The parameter is the delay in seconds to wait for the

        <code>CPONG</code> reply.

        This features has been added to avoid problem with hung and

        busy Tomcat's and require ajp13 ping/pong support which has

        been implemented on Tomcat 3.3.2+, 4.1.28+ and 5.0.13+.

        It will inrease the network traffic during the normal operation

        which could be an issue for you, but it will lower down the

        traffic in case some of the cluster nodes are down or buys.

        Currently this is in effect only for AJP.

    </td></tr>

    </table>