Update changelog

Author: mikebronner

Diff for: CHANGELOG.md

@@ -4,6 +4,13 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [0.2.1] - 2017-09-29
+### Added
+- additional unit tests for checking caching of lazy-loaded relationships.
+
+### Fixed
+- generation of cache key for queries with where clauses.
+
 ## [0.2.0] - 2017-09-24
 ### Changed
 - approach to caching things. Completely rewrote the CachedBuilder class.