Update changelog

Author: emodric

doc/CHANGELOG.md

@@ -6,6 +6,10 @@ 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/).
 
+## [1.0.3] - 2017-04-21
+### Added
+- Symfony 3.x compatibility
+
 ## [1.0.2] - 2017-04-18
 ### Added
 - marked bundle as `ezplatform-bundle` in composer.json