Unit test framework for the generation rules code in the workspace builder

[vaterlaus]

Leverage the new dump/load facility for the resource database to load a predictable resource test fixture to run the generation rules against. Then there needs to be a framework for running just the generation rules logic and verifying that the expected SLX output files were generated.

This doesn't include write a full suite of generation rules unit tests, just one or two as a proof of concept of the framework for writing further tests.