Created Issue: Modify AsyncEntitySetController's actions/methods to accept CancellationToken [943]

Modify AsyncEntitySetController's actions/methods to accept CancellationToken.

http://aspnetwebstack.codeplex.com/SourceControl/changeset/view/ce7261f550e3#src/System.Web.Http.OData/OData/AsyncEntitySetController.cs

Yeah, this would be a breaking change, but couldn't find another way to grab the CancellationToken from within the controller.