Update CHANGELOG

CHANGELOG.md

@@ -5,6 +5,18 @@ 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).
 
+## v4.0.0, 2021.04.25
+
+### Changed
+
+- #30 - Adapt puppet to modification of bin/setup file
+- #29 - Enable clock synchronization (required for OTP)
+- #28 - Use Europe/Paris timezone
+
+### Fixed
+
+- #27 - Remove unnecessary Tmux dependency
+
 
 ## v3.0.0, 2020.11.26