Add invalid host names to the error logged by UserDataHelper

git-svn-id: https://svn.apache.org/repos/asf/tomcat/tc8.0.x/trunk@1831575 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/webapps/docs/config/systemprops.xml b/webapps/docs/config/systemprops.xml
index d8290f4..6773868 100644
--- a/webapps/docs/config/systemprops.xml
+++ b/webapps/docs/config/systemprops.xml
@@ -556,6 +556,7 @@
          <li>too many headers, too many parameters (hitting
            <code>maxHeaderCount</code> or <code>maxParameterCount</code> limits
            of a <a href="http.html">connector</a>).</li>
+         <li>invalid host names</li>
          </ul>
          <p>Other errors triggered by invalid input data may be added to this
          system in later versions.</p>