Add 4.2.0 to CHANGELOG
Add 4.2.0 to CHANGELOG

(cherry picked from commit 693ce77994e0c826988ee0370831cd2dc3237d8b)

sly7-7/ember.js,emberjs/ember.js,emberjs/ember.js,tildeio/ember.js,sly7-7/ember.js,emberjs/ember.js,tildeio/ember.js,sly7-7/ember.js,tildeio/ember.js