Update the changelog for v0.1.0-alpha

Author: andreaskoch

CHANGELOG.md

@@ -4,6 +4,9 @@ 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/).
 
-## [Unreleased]
+## [v0.1.0-alpha] - 2016-12-18
+
+The prototype
+
 ### Added
 - A prototype for the dcsg - A systemd service generator for Docker Compose projects