Update CHANGELOG.md

Author: joshka

CHANGELOG.md

@@ -6,6 +6,11 @@ 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
+
+## [5.4.0-r0] - 2019-02-09
+### Changed
+- Bump JUnit to 5.4.0
+- New version scheme to align better with JUnit
 ### Added
 - Use @JsonConverter to provide actual arguments to tests