Update CHANGELOG.md

Author: vearutop

CHANGELOG.md

@@ -4,6 +4,11 @@ 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).
 
+## [0.2.22] - 2019-12-11
+
+### Added
+- Support to use traits in `PhpClass`.
+
 ## [0.2.21] - 2019-10-25
 
 ### Changed
@@ -25,6 +30,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Fixed
 - Description trimming bug.
 
+[0.2.22]: https://github.com/swaggest/php-code-builder/compare/v0.2.21...v0.2.22
 [0.2.21]: https://github.com/swaggest/php-code-builder/compare/v0.2.20...v0.2.21
 [0.2.20]: https://github.com/swaggest/php-code-builder/compare/v0.2.19...v0.2.20
 [0.2.19]: https://github.com/swaggest/php-code-builder/compare/v0.2.18...v0.2.19