Unit page doesn't load when mathjax is down

Add Mocks to Enrollment API Doc Config

To support UNICODE xblock.location

When mathjax is down studio page doesn't work as
it wait for mathjax to load. I replaced the hard
dependency with soft dependency now unit page can
load with mathjax.

Fix Pylint violations (medium)

I can find no other record of this class.

Add coverage to openedx directory

Don't allow empty string or None for email.

Corrected data sent to E-Commerce API

Disable flaky lettuce test TNL-1679

Remove old comment from file

MA-345 Mobile Enrollment API: add course' Facebook URL.

decorate flaky test

Added Certificates Web/HTML View

fixed a flaky test (acceptance.tests.studio.test_studio_settings_details.SettingsMilestonesTest.test_prerequisite_course_save_successfully)

Awais786/ecom 911 enable noid paid course

Data is now properly encoded as JSON.

Enrolling via E-Commerce API for combined login-registration page

The login-registration page now supports using the E-Commerce API when enrolling users in honor seats (of courses with SKUs).

This new endpoint is intended to replace enrollment API call used on the login+registration page. Instead of directly enrolling students, the view will contact the external e-commerce API (Oscar) to create a new order. Oscar will be responsible for completing the order and enrolling the student.

This behavior will only apply to course modes with associated SKUs. All other course mode enrollments will be processed directly by LMS.

Replace broken logic in import template with working logic in view.

Cleaned up milestones API references