This is primarily to reduce load on MongoDB, where we've lately
had performance problems that we suspect are caused by very
large course structures being evicted from MongoDB's cache. This
may potentially give us a path to better performance as well,
but that's not the goal of this commit.

Surprisingly, LZ4 seemed to actually run more slowly than zlib
for this. Possibly because of some overhead in the Python
bindings? GZip was also surprisingly slow given that it uses
zlib underneath (something like 5x slower).

Use separate cache backend for caching structures.

Abstract out course structure cache.

add datadog metrics for compressed course structure sizes

Since we're using a different cache background, we don't need to have a cache prefix

Use dummy cache backend for tests.

Fallback to default cache if course_structure_cache doesn't exist.

This is primarily to reduce load on MongoDB, where we've lately
had performance problems that we suspect are caused by very
large course structures being evicted from MongoDB's cache. This
may potentially give us a path to better performance as well,
but that's not the goal of this commit.

Surprisingly, LZ4 seemed to actually run more slowly than zlib
for this. Possibly because of some overhead in the Python
bindings? GZip was also surprisingly slow given that it uses
zlib underneath (something like 5x slower).

Use separate cache backend for caching structures.

Abstract out course structure cache.

add datadog metrics for compressed course structure sizes

Since we're using a different cache background, we don't need to have a cache prefix

Use dummy cache backend for tests.

Fallback to default cache if course_structure_cache doesn't exist.

This makes these files importable, and puts them into the new best guess
as to where files should live.

This is compatible with Django > 1.5, and allows us to re-enable the ProfilingDebugPanel

path.py objects report themselves as class objects, which confuses the heck out of
pylint. It tries to match variable names using the class-rgx regular expression
instead of the constant-rgx regular expression, and it doesn't match, so it
throws an error. Not sure how to fix pylint, so we'll just ignore these errors.

Instructors should use Insights instead.

Note that the features in this release are opt-in, and course and video
behavior will remain the same unless a course explicitly opts in.

Major pieces of functionality with this commit:

Allows the listing of a user's enrollments, course videos, and updates. In
order to make a course available for mobile use, course staff must explicitly
set the Course Advanced Setting "Mobile Course Available" to true. Course staff
will always see their own courses through the Mobile API regardless of this
setting, but students will only be allowed to see a course through the Mobile
API if this setting is set to "true". By default, a Course will *not* be
available for mobile use.

This is a Django app for video resource management. It is completely optional,
and is intended to allow video and operations teams to create new encodings of
videos (e.g. low res for mobile) and change CDNs without having to edit course
data directly. Course teams can now use a "EdX Video ID" setting for Videos,
which will leverage VAL. Video units that do not fill in an "EdX Video ID" will
behave exactly as they always have.

* The Mobile API is enabled with the ENABLE_MOBILE_REST_API feature flag.
* VAL is enabled with the ENABLE_VIDEO_ABSTRACTION_LAYER_API feature flag.
* VAL and the Mobile API both require ENABLE_OAUTH2_PROVIDER).
* The Mobile API is a read-only API, but VAL requires database migrations.
* Applications that make use of either the Mobile API or VAL must be registered
  with the OAuth2 provider app in Django Admin.

Also, removed the client-side analytics for logging in.
Ensures that analytics are collected for third-party-auth logins.
Fixed failing tests related to third-party-auth.

Clean up shopping cart processor API.
Fix UUID JSON serialization bug in CyberSource2 implementation.
Update test suite to use new CyberSource2 implementation.
Fix i18n messages in CyberSource2
Enable CyberSource2 implementation by default.

rebased and resolve conficts with cdoge/registration_codes

feature enhancement request: added transaction group name text field to the download buttons as an extra optional query paramerter

This reverts commit 079808ee.

This reverts commit 252038c3, reversing
changes made to 7caf8c53.

Disabled by default.

Disabled by default.

LMS-1296

LMS-1296

Metrics tab shows student data:
  -Count of students opened a subsection
  -Grade distribution per problem

for each section/subsection of the course.

Implemented for both the old and beta dashboard
Controlled by a feature flag 'CLASS_DASHBOARD'
Data is aggregated across all students
Aggregate data computed from courseware_studentmodule

Due to issues with require.js and the latest version of the toolbar.
Also included a note in the requirements file explaining the situation, and what
needs to happen before this can be upgrade properly.

Conflicts:
	lms/envs/dev.py

Due to issues with require.js and the latest version of the toolbar.
Also included a note in the requirements file explaining the situation, and what
needs to happen before this can be upgrade properly.

add trailing comma, restore uncommented state of Mongo panel

Caution! This is backwards incompatible

To mark a language as dark-launched, add it to the DARK_LANGUAGES
django conf setting. To activate a dark-launched language, set he
query parameter `preview-lang` to the language code on any url.

[LMS-2045]
[LMS-2077]
[LMS-2076]

(STUD-1201)

Revert "Specific django-toolbar version (stable released) and update the panels in dev envs"

This reverts commit a465b082.

Revert "Updated settings for devstack django debug toolbar"

This reverts commit 30199e8a.