Add Changelog

CHANGELOG.md

@@ -13,7 +13,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 0022-adopt-encointer-runtime.md) ([polkadot-fellows/runtimes#80](https://github.com/polkadot-fellows/runtimes/pull/80))
 - Feature for enabling debug prints in the Polkadot and Kusama runtime ([polkadot-fellows/runtimes#85](https://github.com/polkadot-fellows/runtimes/pull/85))
 - Added new "Wish for Change" track ([polkadot-fellows/runtimes#184](https://github.com/polkadot-fellows/runtimes/pull/184))
-- Enable Coretime and on-demand on Kusama ([polkadot-fellows/runtimes#159](https://github.com/polkadot-fellows/runtimes/pull/159)
+- Enable Coretime and on-demand on Kusama ([polkadot-fellows/runtimes#159](https://github.com/polkadot-fellows/runtimes/pull/159))
+- Add the Kusama Coretime Chain ([polkadot-fellows/runtimes#212](https://github.com/polkadot-fellows/runtimes/pull/212))
 
 ### Changed