Handle $ref

[xuorig]

Had something started here but decided to pause for the moment until the diff is complete.

It would be real nice to handle JSON references correctly when diffing instead of asking for a dereferenced document like many other OpenAPI tools do.

It does bring certain questions though. Should we diff refs transparently dereferencing as we go? Or we could diff the document itself (meaning a change to a component does not make a difference to a response that links to it, only shows the diff on the component object). In reality I see usefulness in both approaches, maybe that's a "mode" that can be set when running the diff.