Add failing scenarios for address verification of an existing card

[jbrowning]

Adds scenarios for the address portion of #11.

CVV verification scenarios were submitted via #644.

[msherry]

What's the use case for re-verifying the address of an existing card? Re-verifying CVV as a security measure makes sense, but I'm not as sure for address. Is this just to update cards that were tokenized without an address?

[jbrowning]

I imagine it is the same use case as CVV re-verification: security. It's a "lighter" verification than CVV because it does not fall into PCI's scope as far as I know.

[matthewfl]

but doesn't the api already return you the address of the card, checking the address would be comparable to checking for equality with what was previously inputted. I suppose that someone could change the address they have their card on, but I don't see that as a common use case.

[jbrowning]

I do not see a strong use case either. I only created this because @matin mentioned it in #11. Maybe he has a better idea of where this would be useful?