update CHANGES.html

CHANGES.html

@@ -43,6 +43,21 @@ the cracks, unfortunately.  If you, as a user, can suggest improvements
 to this file based on your experience, please contribute a patch or drop
 us a note on ns-developers mailing list.  </p>
 
+<hr>
+<h1>changes from ns-3.3 to ns-3.4</h1>
+
+<h2>new API:</h2>
+<ul>
+<li>ConstantAccelerationMobilityModel in src/mobility/constant-acceleration-mobility-model.h</li>
+</ul>
+
+<h2>changes to existing API:</h2>
+
+<ul>
+<li>StaticMobilityModel has been renamed ConstantPositionMobilityModel</li>
+<li>StaticSpeedMobilityModel has been renamed ConstantVelocityMobilityModel</li>
+</ul>
+
 <hr>
 <h1>changes from ns-3.2 to ns-3.3</h1>