Add explicit 'lms.djangoapps' prefix to all commerce imports, as another
commerce Django app exists at openedx.core.djangoapps.commerce

- Remove usage of django.urls.patterns
- Change urls tuples to lists
- Make all string view names callables
- This is the second of several urls updates for LMS; a work in progress

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.

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.