add django management command for dumping grades to CSV file

Check for None to fix 3.091 progress tab crash

- get_module() contract says it can return None (e.g. if access control check failed)

fixed default tolerance on numericalresponse

Fix openid provider URL matching for usernames with non-word characters

Added an indicator on Progress page when there are no problem scores in a section.

Fix some issues with integer ids in the discussion forum

Adding django-admin/rake command to set the staff bit

Don't function call on null

Feature/victor/per course status

* makes testing easier -- don't need course objects

Victor/capa cleanup

Looks good.  Yes, the code exec part will need more thought, particularly with respect to security.

Don't want to break existing problems.

This reverts commit 811422a1.

- check for known script type instead of ignoring js and perl

Now looks for a status_message.json file, looks for 'global' and ${course.id} keys. Return any global message and any course-specific message, joined by <br>.

fab files need to be updated to use this new format (new filename, possibly also help manage per-course messages, or at least test for valid json)

Added starting_index conf to AssignmentFormatGrader.

Added starting_index conf to AssignmentFormatGrader. Added a bit of forwards compatibility for new grading policies.

added ie warning banner to courseware; displayed by ie conditional style...

Set git push.default to current on the create-dev-env script

Fix error when creating empty associations

move output right/wrong image to top left of each test instead of center

Also renamed some variables to make them more distinguishable