updated CHANGELOG

Author: vimishor

CHANGELOG.md

@@ -2,7 +2,7 @@
 All notable changes to this project will be documented in this file.  
 This project adheres to [Semantic Versioning](http://semver.org/).
 
-## [Unreleased]
+## 0.8.1 / 2016-05-08
 
 ### Fixed:
   - Declining a PR without a `message` parameter caused a 500 response. (issue #43)