Update CHANGELOG.md

Author: DeborahK

CHANGELOG.md

@@ -11,3 +11,4 @@
 - 5/9/16  Updated to Beta 17 including changes to ngFor to use `let` instead of `#`.
 - 5/9/16  Updated to Release Candidate (RC) 1 including all new starter files and change to @angular npm scoped packages. This uses the router-deprecated to match the routing presented in the course.
 - 5/9/16  Updated to the RC component router.
+- 7/1/16  Updated to Angular 2 RC 4.