Fixed note formatting

fix tracking log entry key child-id -> child_id

Enable pure XBlocks to use children in edx-platform

Handle OpenID errors for POST requests.

Expose xmodule_runtime as .runtime if it's set (otherwise, fall back to
the supplied runtime). This causes all blocks to act like XModules when
they have a ModuleSystem, and like XModuleDescriptors if they only have
a DescriptorSystem.

Also fix those tests to correctly wait until the ajax portions have
finished before evaluating the page contents.

Benp/diff cover threshold2

Student profile CSV background task tech debt

ECOM-441

Ensure all user-facing cohort-related strings are internationalized

TNL-565

TNL-566

Some strings were missing i18n calls

When using -p, the underlying diff-quality command will pass that
number as a value for --fail-under.

For example,
  paver run_quality -p 75

Will pass 75 into the --fail-under switch on diff-quality.

Also upgrades diff-cover in order to take advantage of this funcitonality.

Update Contributing documentation with new PR process. OPEN-111

MA-81 Honor video download setting with VAL-enabled videos.

Studio: FIX - Course Rerun Outline Notification Icon Display

Update django-countries to 2.1.2, override country name for Taiwan

Removing the feature flags for new header and footer.

Clean up after track selection experiment

TNL-550

TNL-534

UX-1054

Fix acceptance tests

Updating lettuce tests.

Revert the deletion of the original edx header and footer.

Renaming old header and footers to legacy files.

Add IS_EDX_DOMAIN flag for header.

Updating tests and django main template.

renaming the header files for microsite backwards compat.

Removed Vitalsource e-reader information

Dashboard template cleanup

Make password reset endpoint CSRF exempt