add changelog

CHANGELOG.md

@@ -0,0 +1,19 @@
+# Changelog
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+## [1.1.0] - 2019-10-05
+### Added
+ - Code comments documenting what happens where
+ - Check whether the current path is in a git work tree
+
+### Fixed
+ - Variable name for return value was cargo culted from a git hook, it now makes more sense
+
+## [1.0.0] - 2019-10-02
+### Added
+ - Initial Release