Assign payment account to an app. In bug 869553 a way to create payment accounts was added. This is an API to assign the payment account to the app. That's this drop down: http://cl.ly/image/0p1y1R1t3419
Should this be done as a field on the app resource itself?
turns out setting the payment account pretty much requires price to be set as well, so I went ahead and did that here too. https://github.com/mozilla/zamboni/commit/57eb235