asadiqbal08/WL-420 Updating drag and drop version. 
merging. 

Display correct timezone on timestamp for question submission

Ahsan/removal underscore string from commerce js

Fixes for courseware date formatting/translation.

ECOM-4281

Add skip_clean option to pa11ycrawler

refine from_addr length limits (TNL-4264)

Updated URLs for help topic links that had become stale. Per DOC-2568.

The view for submission history used to grab the timezone from the database (UTC) and
appeded the TIME_ZONE variable after (could be any time zone). Adjusted displayed
timedate to the TIME_ZONE variable. Added unittest checks the localized datetime
object used by submission history for the expected hour difference.

Add referral tracking for new registrations.

Move ENABLE_INSTRUCTOR_EMAIL to admin panel

ECOM-4325

Moves ENABLE_INSTRUCTOR_EMAIL and REQUIRE_COURSE_EMAIL_AUTH from settings files
to admin-accessible configuration models. This allows for the bulk email settings
to be modified without a new AMI deploy. See TNL-4504.

Also updates tests:
    -python tests mock out the new configurations in place of the old settings
    -lettuce test has been moved to bokchoy
        (note that there was some loss of coverage here - the lettuce tests had
        been doing some voodoo to allow for cross-process inspection of emails
        messages being "sent" by the server, from the client! In discussion with
        testeng, this seems outside the realm of a visual acceptance test. So,
        the bokchoy test simply confirm the successful queueing of the message,
        and leaves the validation of sending messages to the relevant unit tests.)
    -bok choy fixture has been added, to replace the settings in acceptance.py
    -lettuce and bok choy databases have been updated to reflect the backend changes

The new default is to have bulk_email disabled, we'll need to call this out in the
next OpenEdx release to ensure administrators enable this feature if needed.

ML-446 / Aligned the labels in login and registration pages

Expire sessions after a password change.

update pa11ycrawler version

Merge pull request #12442 from edx/ibrahimahmed443/WL-450-save-cancel-button-on-instructor-image-path

show Save and Cancel button when admin change Instructor image asset …

show Save and Cancel button when admin change Instructor image asset path from Studio schedule and details page

WL-499 Fix the issue where images do not appear when set through asset linki…

fix the issue where images do not appear when set through asset linkin Studio scheduls and details page

Update thresholds.

Remove tab characters

Integration of Safe Templates Commit into Jenkins

- Handle case when no files are linted
- Skip deleted files for safe commit script
- Add verbose options for safe commit

These asserts are never run.

TNL-4290: Safe template marathon work

These old discussion templates are not referenced in the codebase.

mattdrayer/add-bulk-sku-default-none: Fix MySQL insert error

ECOM-4215 adding setup for new program details page

This is slightly more complicated than it should be since we're using
custom authentication middleware (i.e., not Django's standard
middleware class). We have to check that the session auth hash we have
stored is equal to the request's session auth hash (since the stored
hash is a function of the password). Normally this gets handled in
`django.contrib.auth.get_user`, but due to our caching we don't go
through that function, even in the cache miss case.

ECOM-4288