Added documentation.

git-svn-id: http://svn.igniterealtime.org/svn/repos/openfire/branches/openfire_3_5_2@10415 b35dd754-fafc-0310-a699-88a17e54d16e

src/plugins/clientControl/readme.html

@@ -75,6 +75,10 @@ The plugin will then be automatically deployed. To upgrade to a new version,
 copy the new clientControl.jar file over the existing file.
 </p>
 
+<p><i>Note: Installations using the spark manager plugin will need to uninstall the plugin before installing
+this new plugin.
+</i></p>
+
 <h2>Upgrading from Enterprise</h2>
 
 <p>