Update CHANGELOG.md (#91)

Author: f3ath

CHANGELOG.md

@@ -6,7 +6,13 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ## [Unreleased]
 
-## [2.0.0] - 2018-02-26
-V2 initial release
+## [2.0.1] - 2018-12-31
+### Changed
+- Downgraded min required php version to 7.1
 
-[Unreleased]: https://github.com/json-api-php/json-api/compare/2.0.0...HEAD
+## 2.0.0 - 2018-02-26
+### Added
+- v2 initial release
+
+[Unreleased]: https://github.com/json-api-php/json-api/compare/2.0.1...HEAD
+[2.0.1]: https://github.com/json-api-php/json-api/compare/2.0.0...2.0.1