GitHub #333: Fix MBeanClient example

This fixes the MBeanClient example and adds a unit test to ensure
interface compatibility in future.
diff --git a/org.jacoco.doc/docroot/doc/changes.html b/org.jacoco.doc/docroot/doc/changes.html
index 6aba875..a768e7b 100644
--- a/org.jacoco.doc/docroot/doc/changes.html
+++ b/org.jacoco.doc/docroot/doc/changes.html
@@ -20,6 +20,12 @@
 
 <h2>Snapshot Build @qualified.bundle.version@ (@build.date@)</h2>
 
+<h3>Fixed Bugs</h3>
+<ul>
+  <li>Fix <code>MBeanClient</code> example
+      (GitHub <a href="https://github.com/jacoco/jacoco/issues/333">#333</a>).</li>
+</ul>
+
 <h2>Release 0.7.5 (2015/05/24)</h2>
 
 <h3>New Features</h3>