Shopify/active_merchant — pull request #521 by jduff (2012-12-05 14:57:16+00:00)
Title: AVS response needs to have the keys for the object in the hash returned, even if nil

8cf277a broke this expectation, now there are tests to cover the case.

A MultiResponse test needed to be fixed because of this change as well,
it shouldn't affect the interface or how AVSResult/CVVResult are
returned.

@Soleone, @samuelkadolph for review