improve flexibility in changing Checkout page options (e.g., Contact me with offers)

While most fields on the Checkout page are tied to the checkout process,
"Contact me with offers" (in the code, it's marketing_preference) is not. 

That is, I do think the checkout process is a good place to ask user if
they want to be contacted with offers, but the user's response doesn't
impact the checkout process.

It's likely that organizations will want to include different custom fields
here (e.g., agreeing to terms of service, opting in to newsletters).

I think determining these custom fields should be set through GetPaid's
Configuration views.

Currently (getpaid.core v.7), marketing_preference is part of the schema
for IUserContactInformation. I suspect modifying this schema will cause
something to break. We may need to implement a different way of capturing
marketing_preference and non-essential Checkout page options.

Original issue reported on code.google.com by mcgruff....@gmail.com on 13 Oct 2008 at 12:49

kapilt / getpaid

improve flexibility in changing Checkout page options (e.g., Contact me with offers) #224