Add CHANGELOG.md

CHANGELOG.md

+# CHANGELOG
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
+and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+### Added
+### Changed
+### Fixed
+
+## 1.0.0 - 2019-08
+### Added
+- Initial commit
+
+## x.y - yyyy-mm-dd
+### Added
+### Changed
+### Fixed
+### Deprecated
+### Removed
+### Security