* Add openedx.core.lib.xblock_builtin.get_css_dependencies and get_js_dependencies,
which respect PIPELINE_ENABLED setting when determining dependencies.
* Move new discussion-related Sass files into discussion subdirectory.
* Use "load_unicode" instead of "render_template" to load JS to add to fragment for DiscussionXBlock.
* Remove unused "course" parameter from context for DiscussionXBlock.student_view.
* Add RTL stylesheet for DiscussionXBlock, and enable the block to load correct stylesheet.
* Load MathJax only once, and include code for configuring MathJax in discussion bundle.
* Make sure username renders correctly in DiscussionXBlock response header.
* Move WYSIWYIG Markdown editor styles to _build-discussion.scss.
* Remove unnecessary import of discussion/utilities/v1-compatibility from _build-discussion.scss.
* Keep courseware-chromeless.html in sync with courseware.html.
* Load CSS for discussions on Teams tab. This makes it possible to remove CSS for discussions from Sass files for "Course" tab.
* Load js/src/tooltip_manager.js, jquery.autocomplete.js and jquery.autocomplete.css on "Course" tab.
* Safe template linter reports zero violations on modified files
* Removed some (or most) coffeescript-genereated returns
* Big HTML chunks in JS converted to underscore templates
* Markdown processor - safe tempate linter compatibility
* Fixed double escaping HTML tags in code blocks caused by passing it through postMathJaxProcessor twice
* Removing jQuery.ajax.beforeSend - it might be set globally and this code overrides it (part of 62fa253af6ee384f0766d72cd2d67bcf43697692)
* Avoid resetting Backbone history if already started (part of 9591b526bdd56163de0098099e46e44c566061f5)
* goHome no longer triggers thread:removed event - already triggered up the call stack (part of 9591b526bdd56163de0098099e46e44c566061f5)
* Avoid using beforeSend as it might be set globally (adapted from 2dfe104f3915efa546c85ef277eb75c5abb9b49b)
* Refactor triggering navigation to use constant/method instead of magic strings (part of 4843facd507b1cee8712bf10e96ff6c25c98bca2)
* Switching to using jQueyr.prop instead of jQuery.attr
* Fixed email notifications enable/disable (adapted from 8a7f022)
* Load thread if requested thread isn't loaded yet (adapted from e28dde32169b388235030dba945366f4c13e565f)
* Added ability to set custom css classes on search messages (adapted from b2e4c18905d7c7560838e264d6b218a3c4c6dc1f)
* Actually rerendering view with new model data when it is loaded/changed
