Update changelog

Author: mblaschke

CHANGELOG.md

@@ -2,12 +2,18 @@
 All notable changes to this project will be documented in this file.
 This project adheres to [WebDevOps.io Dockerfile](https://github.com/webdevops/Dockerfile).
 
+## [0.21.5] - 2016-03-24
+### Added
+- Fixed permissions automatically for /tmp if mounted as volume
+- Added error checks for samson service script
+
 ## [0.21.0] - 2016-03-20
 ### Changed
 - Improved entrypoint startup time
 - Removed entrypoint ansible provisioning if not needed
 - Added java-jre and latest npm for samson-deployment
 
+
 ## [0.20.0] - 2016-02-24
 ### Added
 - Added sqlite to base images