Update Release notes with improvment

Author: Steven T. Cramer

Documentation/ReleaseNotes/Realease2.0.0.md

@@ -5,8 +5,13 @@ title: Release 2.0.0
 
 ## Release 2.0.0
 
+### Breaking Changes
 Since have moved from preview builds to release, and ReduxDevTools should be disabled in production, we are changing the default option setting to be disabled.
 
 `BlazorStateOptions.UseReduxDevToolsBehavior` now defaults to false; 
 
 See [Migrations](xref:BlazorState:Migration1-2.md) for how to migrate existing projects from 1.0 to 2.0.
+
+### Improvements
+
+`Action`s and their `Handler`s should be nested classes of the `State` they act on. Previously the developer could forget this and it would take some time to figure out the problem (I know I did it.).  Now RenderSubscriptionsPostProcessor with throw an exception if the IAction is not nested within an IState.