Check existence of JSON data from both catalog and LMS course API

Revert use of catalog for basket page.

This reverts commit b1250ba5.

This reverts commit 72386e07.

Check for top level image null

Use catalog service for course info.

Fixed course save button not redirecting

[SOL-2004] Display seats instead of courses in catalog preview API endpoint.

Rename start and end datetime parameters; Refactor update dictionary creation method;

[SOL-2038] Add a check if email_domains are in coupon update data before updating it

Remove API constants

Fix Coupon Acceptance Tests

Add a list of email domains to an offer for validation at redemption.

Updated translations

[SOL-2033] Change voucher list to raw ID list in basket details admin page.

SOL-1991: Create Management Command for adding Site and SiteThemes

Remove attempts to reverse catalogue URLs from templates

We don't use URLs from the catalogue app. ECOM-5204.

[SOL-1989] Remove duplicate invoices

Upgrade to edx-auth-backends 0.5.2

SOL-1926: Add organization filter on courses.

This resolves migration issues related to the changing of the app's name.

ECOM-5232