Updates CHANGES.html and RELEASE_NOTES

CHANGES.html

@@ -63,7 +63,7 @@ us a note on ns-developers mailing list.</p>
 
 <h2>Changed behavior:</h2>
 <ul>
-<li></li>
+<li>Sending a packet through Ipv4RawSocket now supports checksum in the Ipv4Header. It is still not possible to manually put in arbitrary checksum as the checksum is automatically calculated at Ipv4L3Protocol. The user has to enable checksum globally for this to work. Simply calling Ipv4Header::EnableChecksum() for a single Ipv4Header will not work.</li>
 </ul>
 
 <hr>

RELEASE_NOTES

@@ -24,6 +24,8 @@ New user-visible features
 
 Bugs fixed
 ----------
+ - bug 1479 - When the Ipv4RawSocket "IpHeaderInclude" Attribute set true,
+              Ip Checksum error
  - bug  976 - wifi-wired-bridging regression test fails because of 
               rounding errors in mobility model
  - bug 1284 - ./test.py performance tests do not exist