More accurately, this creates a 4th shard because the
last shard is always the default.

Revert "SUST-35 Implementation of course_key_from_string_or_404 to return course_key or raise a 404"

ECOM-4292

This supports a number of their new Error features.

This reverts commit 785b752d.

TNL-4358

TNL-4335

MA-2305

ECOM-4281

Introduces a utility class for gauging a user's progress towards program completion. Progress data is passed to the ProgramListFactory. ECOM-3200.

The JWT includes the user email and username, along with details pulled from the original access token (e.g. scope, expiration).

ECOM-4221

ECOM-3437