Update discussion.md

- fixed typo
- roles 'moderator' and 'administrator' are explained as bullet points.
styled rubric, dividers between sections
merge edit cleanup, nothing new
Translate messages early
Check that content-type starts with application/json

When Chrome sends the AJAX request to add a user to the course team, it sets the
Content-type to "application/json". However, when Firefox sends the same request,
it sets the Content-type to "application/json; charset=UTF-8". This commit only
checks that the Content-type begins with "application/json", not is identical
to it; that way, Firefox can play, too.
Merge pull request #566 from edx/db/i18n-lib-update

Update Babel and Transifex libraries
Auto-enroll course staff to fix "View Live".

STUD-554

Code review feedback.
Merge pull request #579 from edx/db/course-team-role-fix

Fix for STUD-582
tie in the normal courseware link url rewriting in capa module since that presents HTML via an Ajax callbacks and not via module_render.py
Check that content-type starts with application/json

When Chrome sends the AJAX request to add a user to the course team, it sets the
Content-type to "application/json". However, when Firefox sends the same request,
it sets the Content-type to "application/json; charset=UTF-8". This commit only
checks that the Content-type begins with "application/json", not is identical
to it; that way, Firefox can play, too.
redirects lms landing page to student.views.index if there is no marketing site

resets the cms edge redirect to '/'
Merge pull request #582 from edx/fix/adam/redirect

Fix/adam/redirect
adjustment to sidebar help text on PDF textbook page in studio
have the Files and Upload pages surface a 'portable_url' which uses the /static/ shorthand which is more portable across course runs
don't attempt to do URL rewriting in the import step, let the LMS/CMS runtimes do it on the fly on reference
add unit tests around asserting that /static/ links are not re-written on import
remove redudent asset_url return value when uploading files
add a test for the static url generation
alter the HTML editor so that it can do the /static/ <--> /c4x/ substitutions when toggling back and forth between the visual and advanced editors
fix cut/paste comment confusion