Support for child stories added to linked stories in Rally

When the following Aha! to Rally mapping is used:

Features -> Features
Requirements -> Stories

Requirements can be pushed to Rally and stories are created, then child stories can be added to those stories in Rally. However, if the linked requirements get moved to a different feature in Aha!, the stories that have child stories in Rally will not be moved to the corresponding feature.

Ideally these stories should move to the corresponding feature to keep everything in sync.