Merge pull request #5427 from edx/renzo/profile-page-preferred-language

Allow changing of language preference from profile page
Added default font to a  list of available fonts in text editor XModule
Added acceptance test scenario to test for existense of "Default" font and all tinyMCE built-in fonts
Updated AUTHORS
Fixed multiple JsInput's in problem.
TNL-269
Merge pull request #5330 from edx/waheed/tnl269-fix-multiple-jsinput

Fixed multiple JsInput's in problem.
Merge pull request #4930 from e-kolpakov/master

Fix for TNL-147
Merge pull request #5139 from edx/benp/enforce-pep8-pylint-threshold

Paver: fail if pylint/pep8 violations threshold is breached.
Tweak to old header styles to fix login button
Show cohorts on the new instructor dashboard

TNL-161

Remove placeholder text
LMS: revises membership UI layout on instructor dashboard
LMS: adds static cohort group management UI to the Instructor Dashboard
TNL-160 Default cohorts, automatically created.
correcting needed markup for cohort management static UX template
addressing FED feedback
TNL-328 Server-side work for displaying type of cohort.
TNL-329 Client-side work for displaying cohort description.
Adding static rendering for cohort group creation UI

* adding styling/markup for "add new group" controls, messages, and form
* small FED and UI changes to overall cohort management UI
adding copy revisions and light styling support for cohort management
Support adding students to a cohort via the instructor dashboard.

TNL-163
converting instructor dashboard message UI to use .is-hidden vs.is-shown stateful CSS classes
LMS: revising .is-hidden utility class to be used at a global level