Add one-to-many Payment relationship to Order.
Deprecate the old getPayment and setPayment methods.
Fix comments.
Update payment listener and state resolver to loop through all payments.
Fix comments.
Change security token model to Payment.
Update last payment only.
Payment details bug fix.
Change OrderStatusAction to PaymentStatusAction.
Minor bug fix.
Fix comments.
Update migration class.
Fix specs.
Add new tests to cover payment states.
Fix more tests.
Add getLastNewPayment.
Update PayPal INVNUM and Be2Bill ORDERID format.
Fix comment.
Rename CaptureOrder classes to CapturePayment.
Merge pull request #1203 from kayue/feature/payment-order

Multiple payments support.