Update CHANGELOG.rst

CHANGELOG.rst

@@ -5,6 +5,12 @@ These are notable changes in edx-platform.  This is a rolling list of changes,
 in roughly chronological order, most recent first.  Add your entries at or near
 the top.  Include a label indicating the component affected.
 
+Common: enhanced shib support, including detection of linked shib account
+at login page and support for the ?next= GET parameter.
+
+LMS: Experimental feature using the ICE change tracker JS pkg to allow peer 
+assessors to edit the original submitter's work.
+
 LMS: Fixed a bug that caused links from forum user profile pages to
 threads to lead to 404s if the course id contained a '-' character.