EDUCATOR-1204 | can always view certs when ready for self-paced courses; don't hide cert buttons; update messaging.

date has passed

The verified seat upgrade deadline for self-paced course runs is now
dependent on when the learner was first able to access the content--the
latest of enrollment date and course run start date.

LEARNER-2017

LEARNER-1854

This includes several general enhancement in addition
to the fixes for unified_course_view:
1. Add support for default when no waffle flag defined.
2. Add support for table_blacklist to assertNumQueries.
3. Rename flag to 'course_experience.course_outline_page'.
4. Change flag default to True when it is not defined.

[LEARNER-311] Enable a purchase button on the Program page - platform (WL)

PSA was monolothic, now split, with new features, like
a DB-backed partial pipeline. FB OAuth2 version also upped.

Partial pipelines don't get cleared except when necessary.
They persist for special cases like change of browser while
still mid-pipeline (i.e. email validation step).

Refactor, cleanup, and update of a lot of small things as well.

PLEASE NOTE the new `social_auth_partial` table.

This sock sits at the bottom of both the home and the course content pages. It allows the user to click a 'Learn More' button to open a panel that allows the user to navigate to the upgrade checkout page. The sock is only shown for users that have not yet upgraded in a course that has a verification upgrade date that has not yet passed. Python tests cover the various course mode and upgrade dates.

LEARNER-877

The read_cached_programs switch was used to control the release of changes for reading programs exclusively from the cache. With those changes stable, the switch is no longer necessary.

LEARNER-382

Also add it to the course home page.

LEARNER-609

ECOM-7688

LEARNER-76

Turn override into a sensible default that calls both of the
for_request and in_model submethods, which are themselves still
avaiable if needed.

Add a new waffle switch that allows us to assume zero grades for
learners who have no entry previously recorded, and another to
disable persisting grades for unengaged learners.

TNL-6691

LEARNER-394

ECOM-7532

TNL-6674