Payment portal should allow EE license to be purchased at same time as instance

This may require integration of the GitHost stripe account into our general Zuora account.

Basically, on our end, we always need to be able to see the distinction between charges for / payments for license vs. usage. Usage is billed monthly since it can fluctuate, licenses billed annual. In https://gitlab.com/gitlab-com/githost/issues/30, at least one customer asks for an easy way to add users on the fly. That's perhaps one step too far at the moment?

@rdavila can you help us format the payment portal and process so that everything is easy for the customers with a single credit card swipe?

\cc @wilsonlau @pmachle @dblessing @ahanselka

License and usage will have a different sku. Adding users to an existing subscription would not be a problem.

assigned to @rdavila

added Payment and licensing label

cc: @francisaquino

Example of customer who expected this behaviour and was frustrated by the lack of clarity here. https://gitlab.zendesk.com/agent/tickets/57535

\cc @cpallares please add more links to more tickets on this topic if/when they appear. Also cc @dblessing :-)

added customer label