Update xblock-mentoring.

Update reference to the xblock-mentoring repository.

A bug where answers containing the string "??" would get mangled by jQuery has been fixed in xblock-mentoring.
Modify certificates_show_before_end_date behavior

Hide the certificate notification box when there's
no certificate information, even when the flag
certificates_show_before_end_date is turned on.

ECOM-11
removing "flaky" plugin, since it is not reporting failures properly
Updating ORA2 hash for hotfix August 5th, 2014
ORA2 hotfix 2014-08-06
LMS-11177 Add Split to configuration settings.
LMS-11179 Fix Assets with Split
LMS-11019 Add feature flag to create Split Course
LMS-11168 Support for removing versions and branch in Split, Mixed, and SQL.
Make default_store thread-safe.
Fix get_courses.
Make Split Course work with new Publishing UI.
Update AUTHORS file
Address code coverage and quality.
Catch InvalidKeyError in course_id_from_url().

LMS-9663
Merge pull request #4747 from rocha/update-authors

Update AUTHORS file
Add tooltip manager in Studio.
ORA2 release-2014-08-08T13.47
Merge pull request #4744 from edx/clytwynec/remove_flaky_decorator_from_tests

removing "flaky" plugin, since it is not reporting failures properly
Merge pull request #4752 from edx/will/ora2-release-2014-08-08T13.47

ORA2 release-2014-08-08T13.47
Basic fix for upgrade text bug