updated changelog

CHANGELOG.md

@@ -4,15 +4,21 @@ 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/).
 
-## 0.3.0 - 2016-12-26
+## [0.3.1] - 2017-03-08
+
+### Fixed
+
+* Null reference bug
+
+## [0.3.0] - 2016-12-26
 
 ### Changed
 
 * Updated tests
 * Updated to `http-interop/http-middleware#0.4`
 * Updated `friendsofphp/php-cs-fixer#2.0`
 
-## 0.2.0 - 2016-11-27
+## [0.2.0] - 2016-11-27
 
 ### Changed
 
@@ -21,3 +27,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ## 0.1.0 - 2016-10-08
 
 First version
+
+[0.3.1]: https://github.com/middlewares/debugbar/compare/v0.3.0...v0.3.1
+[0.3.0]: https://github.com/middlewares/debugbar/compare/v0.2.0...v0.3.0
+[0.2.0]: https://github.com/middlewares/debugbar/compare/v0.1.0...v0.2.0