Improve PSE's Import/Export/Copy functionality to allow conversion of referenced elements to standalone elements

Presently, when copying sections of an AF hierarchy that contain dependencies (element templates, referenced elements, attributes that use these references), the dependencies that are located under the AF branch being exported will successfully be replicated on the destination. For referenced elements under the branch, they will not properly be replicated and will be missing from the destination.

This happens because the referenced element actually exists at a different point in the AF hierarchy, and recreating it in a different place can lead to references and subsitution parameters not resolving properly. If the user is okay with that caveat, it would be great to have an option for PSE to replace those element references with newly created, elements and import their templates under the imported AF branch to allow for exporting and importing smaller sections of a hierarchy for testing purposes.