clarify the status of ./waf --regression removal

CHANGES.html

@@ -49,7 +49,11 @@ us a note on ns-developers mailing list.  </p>
 <h2>Changes to build system:</h2>
 <ul>
 <li><b>Regression tests are no longer run using waf</b>
-<p>All regression testing is now being done in test.py.  As a result, reference traces are no longer needed in ns-3 to perform regression testing.
+<p>All regression testing is now being done in test.py.  As a result, a 
+separate reference trace repository is no longer needed to perform 
+regression tests.  Tests that require comparison against known good traces
+can still be run from test.py.  The --regression option for waf has been
+removed.
 </p>
 </ul>
 

RELEASE_NOTES

@@ -38,6 +38,15 @@ New user-visible features
      will allow an initial call to SetPosition () (before any waypoints
      have been added) to be treated as the first waypoint.
 
+   - Regression testing is now completely performed within test.py
+     rather than a separate "./waf --regression" that consults
+     reference traces in the ns-3.x-ref-traces directory.  In most
+     cases, the example programs whose traces were included in 
+     ns-3.x-ref-traces have a corresponding test called from the
+     test.py program.  It is still possible to write trace-based
+     regression tests but they are now called from the test.py
+     program.
+
 Bugs fixed
 ----------
 The following lists many of the bugs fixed or small feature additions