Show price/method data for all available payment regions (bug 884443)

This branch shows both the local currency and the billing method for available regions as returned by the api.

This changes local prices to always show along with the billing method as it's useful data for informing the user as to whether to check that region or not.

I used data sent from the view in a data attr as json - not having used that convention before I'd appreciate someone sanity checking that's all ok.

I've also switched away from changing the type of the radio button for free-in-app to get rid of a jqmigrate warning.