Switch to using an `NSRecursiveLock` instead of @synchronized within `RKEntityByAttributeCache`. Avoid a potential deadlock when handling a `NSManagedObjectContextObjectsDidChangeNotification` notification
Improve cancellation behaviors for in-progress `RKManagedObjectRequestOperation` instances
Reorder `RKTestFactory` dispatching of the tear down block so that you have reference to the current environment to perform the tearDown
Relax assertion in `RKSearchIndexer` so that it does not fail in the event a `nil` managed object is returned by `existingObjectWithID:error:`