Link to bug num in bug database with \bugid{num}

CHANGES.html

@@ -109,6 +109,10 @@ us a note on ns-developers mailing list.</p>
 
 <h2>Changes to build system:</h2>
 <ul>
+  <li> Make references to bug id's in doxygen comments with
+    <tt>\bugid{num}</tt>, where <tt>num</tt> is the bug id number.  This
+    form will generate a link to the bug in the bug database.
+  </li>
 </ul>
 
 <h2>Changed behavior:</h2>