* Add Parallel activity * Update polymorphic converter to handle null values * Add support for converting ExpandoObject into target type * Update models in Webhooks module * Add Onboarding sample projects * Handle null values in converter * Add error logging to webhook invoker * Allow activity resumption callbacks to be static * Handle $ref when serializing expando objects
* Incremental work * Implement samples * Update samples * Small refactorings Closes #3592