Dhm/import split test

Instructor Dash: Display message when no tasks running 

This commit adds a message to the instructor dashboard that is displayed when
no instructor tasks are currently running. This message is displayed where the
instructor pending tasks table would normally be placed, and is replaced
with the table when there are running tasks.

Anton/sync groups and verticals

set root logging level for acceptance tests to ERROR

Add a request-token to identify which xblock html was rendered as part o...

Auto enroll students even if there are multiple course modes

[STUD-2903]

Update i18n-tools

make unit tests respect mongo port/host settings (with default)

Add session middleware to an external auth test to fix a test failure with the auto-registration AB-test changes

Use English for the marketing site buttons in an edx-controlled domain

Update the reference to gsehub/xblock-mentoring#4

Email content history fix and additions

This addresses a bug in the email content history table where
"Unknown" was displayed in the number of emails sent column if any sort of
failure occurred during email sending. This behavior has been editted so now
the number of emails that failed to send is displayed, along with the number
of emails that were successfully sent. If the email task is still pending,
"0 sent" is displayed.

As a small addition, the table now also includes the authors of previously
sent emails, and the modal window for an email also displays its author.

Minor i18n fixes prompted by translators

Release

Hotfix/2014 08 14

Update django-splash.

Generalizing CONTRIBUTING.rst to all repos

STUD-1999

STUD-2090

The new release supports wildcards in path exclusion rules.

Check REQUEST_CONTEXT.context exists before accessing it.

LMS-11226

BLD-1125: Validate content experiments after managing a group.

Include Optimizely on the platform

Release edx-jsme 1.0