Support parent-child linking across workspaces and Rally projects through integration.

In the Aha! we have Features that reference a parent Epic in another workspace. In Rally we have portfolio items that are children of a Capability in another project. This cross workspace/project relationship is supported in Aha! and Rally, but the integration does not current support maintaining the parent-child linkage.

It's not feasible to manually link the parents to their children in each system as it causes too much potential for error.