convert release_notes to changelog

Author: TheAngryByrd

CHANGELOG.md

@@ -6,10 +6,34 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
-## [0.1.0] - 2017-03-17
+
+## [0.2.2] - 2019-10-02
+
+### Changed
+- MINOR: Adds ArrayPool for lower GC pressure.  Netstandard2.1 only
+
+## [0.2.1] - 2019-09-12
+
+### Changed
+- MINOR: Replace Memorystream with RecyclableMemoryStream to help reduce Large Object Heap allocations (https://github.com/TheAngryByrd/FSharp.Control.WebSockets/pull/3)
+- MINOR: Adding Benchmarks (https://github.com/TheAngryByrd/FSharp.Control.WebSockets/pull/3)
+
+## [0.2.0] - 2019-05-24
+
+### Added 
+- Doc Comments for all public functions
+### Changed 
+- BREAKING: API Changes
+
+
+## [0.1.2] - 2019-05-23
+### Changed
+- Update Nuget Description
+
+## [0.1.1] - 2019-05-23
 First release
 
 ### Added
-- This release already has lots of features
+- Initial Release
 
 [0.1.0]: https://github.com/user/MyCoolNewLib.git/releases/tag/v0.1.0