Upstream refactor

This patch is based on two other patches that should be merged first:
    
    https://github.com/CiscoSystems/grizzly-manifests/pull/33

and

    https://github.com/CiscoSystems/grizzly-manifests/pull/34 (this could be submitted separately, but I would prefer if they were merged in order)

This patch is the first attempt to resolve the example manifest and core.pp with the upstream modules.