Update CHANGELOG.md to v2.1.4

Author: Jason Bolla

CHANGELOG.md

@@ -3,6 +3,11 @@ All notable changes to this project are documented in this file.
 
 The format is based on [Keep a Changelog](http://keepachangelog.com/).
 
+## 2.1.4 - 2018-04-09
+
+## Added
+- Add support for Public IPs. More details can be found [here](https://github.com/oracle/terraform-provider-oci/blob/master/docs/core/public_ips.md).
+
 ## 2.1.3 - 2018-03-29
 
 ## Added