Update CHANGELOG

CHANGELOG.md

@@ -9,6 +9,15 @@ and this project adheres to [Semantic Versioning][semver].
 
 ### Added
 
+### Changed
+
+### Fixed
+
+
+## [0.4.0] - 05/01/2020
+
+### Added
+
 - Git method to create orphan branch ([129])
 - Added updater check which verifies that metadata corresponding to the last commit has not yet expired ([124])
 - Additional updater tests ([124])
@@ -216,7 +225,8 @@ and this project adheres to [Semantic Versioning][semver].
 [keepachangelog]: https://keepachangelog.com/en/1.0.0/
 [semver]: https://semver.org/spec/v2.0.0.html
 
-[Unreleased]: https://github.com/openlawlibrary/pygls/compare/v0.3.1...HEAD
+[Unreleased]: https://github.com/openlawlibrary/pygls/compare/v0.4.0...HEAD
+[0.4.0]: https://github.com/openlawlibrary/pygls/compare/v0.3.1...v0.4.0
 [0.3.1]: https://github.com/openlawlibrary/pygls/compare/v0.3.0...v0.3.1
 [0.3.0]: https://github.com/openlawlibrary/taf/compare/v0.2.2...v0.3.0
 [0.2.2]: https://github.com/openlawlibrary/taf/compare/v0.2.1...v0.2.2