Tag version 0.1.0 in the changelog

Author: stevegrunwell

CHANGELOG.md

@@ -4,7 +4,7 @@ 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]
+## [Version 0.1.0] — 2020-09-25
 
 Initial public release of the package, with the following traits:
 
@@ -14,3 +14,4 @@ Initial public release of the package, with the following traits:
 
 
 [Unreleased]: https://github.com/assertwell/phpunit-global-state/compare/master...develop
+[Version 0.1.0]: https://github.com/assertwell/phpunit-global-state/tag/v0.1.0