Add configuration model for enrollment refunds.
Use order info from otto in refund window calculation
Delete dupe tests. Extend tests to include window tests
Move ecom client from lib to djangoapps in openedx
The receipt page now retrieves data for orders instead of baskets. Going forward baskets will be deleted after an order has been placed, so there should be no permanent references to baskets. Orders will continue to be persisted permanently.
ECOM-2653
These endpoints are currently for internal use only, but should be versioned nonetheless; Drupal will begin using the basket creation endpoint soon. No functionality has been changed. XCOM-494.
