Feature/add node stores

Added node store
Added unit tests for node store
TODO: TenantID is not implemented
TODO: Have not refactored node code out of cluster store
I don't really like this, since it is technically incorrect, but let's go ahead and up them in until we clean things up a bit more and rearrange the plugins, since they won't be shipping with the provisioner in 0.9.8 and beyond.