Request parameter for different card response options

[ianbjacobs]

We have discussed different response payload options related to card data:

• Token with cryptogram
• Token without cryptogram (does this amount to something like Basic Card?)
• Reference so that PSP can retrieve token with cryptogram

Presumably we need a request parameter for some subset of these options.

[ianbjacobs]

I believe that this issue is being addressed in issue #14 and #17 so I am closing this one.