Update CHANGELOG.md

Author: Andy Lo-A-Foe

CHANGELOG.md

@@ -4,6 +4,10 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
+## v0.2.0
+
+- Upgrade to Terraform 0.12.x
+
 ## v0.1.0
 
 - Initial implementation