add updateCart/trackPurchase to changelog

Author: roninopf

CHANGELOG.md

@@ -3,6 +3,10 @@ All notable changes to this project will be documented in this file.
 This project adheres to [Semantic Versioning](http://semver.org/).
 
 ## 6.3.2
+#### Added
+- `updateCart` has been added to the SDK
+- `dataFields` have been added as a field to `CommerceItem`
+
 #### Removed
 - The following calls that were previously marked as deprecated have been removed:
   - `IterableAPI.track(inAppOpen messageId: String)`