set max enrollment for downloads to 200

Add AUTOMATIC_VERIFY_STUDENT_IDENTITY_FOR_TESTING flag so that acceptance tests can run through certificate identity verification flow.

There's no need to display a traceback for every failed content load,
the comment before the log line even says so.

The exceptions shown before tests are run are because of the eager
initialization of the modulestores.  They don't need to be initialized
then, that just speeds the responsiveness of servers.  Putting off the
initialization means they get inited as needed, and the log lines get

With tests, some settings changes
(all should default to not breaking anything for edx)

Added styling for shopping cart User Experience
- Styled shoppingcart list page
- Styled navigation shopping cart button
- Styled receipt page
- Styled course about page for shopping cart courses

Addressed HTML/SCSS issues

Remove offending body class and unnecessary sass changes

Addresses many review comments on stanford shopping cart

* framework for generating order instructions on receipt page
  in shoppingcart.models
* move user_cart_has_item into shoppingcart.models
* move min_course_price_for_currency into course_modes.models
* remove auto activation on purchase
* 2-space indents in templates
* etc

revert indentation on navigation.html for ease of review

pep8 pylint

move logging/error handling from shoppingcart view to model

Addressing @dave changes

* Add unit test coverage for this "exclusion from tracking" logic
* Exclude based on regex match instead of raw string comparison
* Exclude heartbeat requests from tracking

Also added datadog application to commom django apps and set it to use
a local statsd server by default.

* Fix open redirect vulnerability
* Add Logging To AUDIT_LOG : Note I had to change existing tests
  that mocked AUDIT_LOG with this
* Use external_auth.views.SHIBBOLETH_DOMAIN_PREFIX in student.views
* Add a bunch of documentation
* PEP8 / Pylint

Conflicts:
	cms/djangoapps/contentstore/views/course.py
	common/lib/xmodule/xmodule/tests/test_combined_open_ended.py
	lms/envs/common.py

A one-click way of getting to editing the course

STUD-669.

Includes Data + Schema migrations for optout email -> user.id change.
Note that migrations should be reversible.

Adds a new Email link to the instructor dashboard for frontend interface to send
email to course members. Adds a feature flag ENABLE_INSTRUCTOR_EMAIL to toggle this.
Creates a new djangoapp bulk_email that handles this action by getting the recipient
list and batching the emails to different celery tasks to do the actual sending.
Requires lynx package to convert HTML email to plaintext. Handles SMTP errors by
retrying or falling through to the next email. Adds the option to opt out of course
specific emails in the user dashboard with an Email Settings link for each course.
Uses severable configurable settings with defaults. DEFAULT_BULK_FROM_EMAIL
specifies the from address for email. EMAILS_PER_TASK specifies the number of emails
each celery task takes on. EMAIL_HOST, EMAIL_PORT, EMAIL_HOST_USER,
EMAIL_HOST_PASSWORD, and EMAIL_USE_TLS for the SMTP email backend settings.

Co-authored-by: Akshay Jagadeesh <akjags@gmail.com>

* Make currency a property of the Order (for validation purposes)
* Remove null=True from Char fields
* Use InheritanceManager for subclassing OrderItem
* Change VerifiedCertificate to better handle some new use cases
* Cleaned out old migrations
* Tests!

* Make currency a property of the Order (for validation purposes)
* Remove null=True from Char fields
* Use InheritanceManager for subclassing OrderItem
* Change VerifiedCertificate to better handle some new use cases
* Cleaned out old migrations
* Tests!