Update changelog

Author: mikebronner

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/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [0.2.8] - 2017-10-17
+### Updated
+- code with optimizations and refactoring.
+
 ## [0.2.7] - 2017-10-16
 ### Added
 - remaining unit tests that were incomplete, thanks everyone who participated!