Removed unnecessary line in change_subscription_plan_spec
updated subscription js forms to pass in quantity
add quantity to async params if subscription is being created
Added change_quantity method to subscriptions_controller
Added old_quantity to Payola::Subscription
quantity_changed event is executed now
quantity is set when subscription is created now
Added change_quantity to routes
Added test for change_quantity, fixed old tests that weren't actually testing anything (the ones testing if they could modify the subscription were always calling cancel, not just change_card and change_quantity)
Added quantity to dummy app form
Added Payola::ChangeSubscriptionQuantity, similar to Payola::ChangeSubscriptionPlan
Added testing for Payola::ChangeSubscriptionQuantity
wrong variable name, changed form to data_form
Added quantity to create_params