Added tests to catch said bug.

Fixed some pylint violations.

Fixed bug when user votes w/o permission - now displays a friendly error message instead of failing.

Fixed bug when hinter module displays a hint, then is asked to display nothing.  (Used to not update in this case.)

Teach rake test_$lib to understand specific test names

Incidental functionality improvements from Next Gen Modulestore work

Make server errors return JSON if requested via AJAX

On Linux, coffeescript refuses to compile unless the `catch` keyword has an error
variable to bind to. On Mac, it works just fine either way. Go figure.

Moved xml_store_config, mongo_store_config, and draft_mongo_store_config...

Moved xml_store_config, mongo_store_config, and draft_mongo_store_config to xmodule/modulestore/tests/django_util.py
Removed some repeated instances of xml_store_config.
Reverted some changes to mongo_store_config so each modulestore gets it's own uuid.

Felix/hinter2

This reverts commit 74d20c20.

Made abtests display its children in the right order.

DraftModuleStore was originally designed as a mixin, but never used that
way, and with the upcoming changes to use the versioned module store,
never will be. This changes removes a circular dependency between
mongo.py and draft.py.

Fixed various commenting things.

Removed an unused function in the crowdsourced module coffeescript.

Improved commenting in hint_manager.

Fixed pep and pylint violations.

Show a confirmation on asset delete. Fixes STUD-375.

Edited text of crowdsourced hinter template to Piotr's suggestions.  Added some HTML formatting to same.

Expanded test coverage a little.

Expanded tests of hint_manager.

Enabled the hint_manager by default in development environments.

Fixed broken tests.  Made the hint manager enabled in testing environments - this lets us test the hint manager.

Began enforcing one-vote-per-person.  This can be disabled with debug="True" in the <crowdsource_hinter> tag.

Started tests of the hint manager.

Chiseled a little at writing template tests.

Hinter now displays vote count after voting.

Began testing templates.

Fixed some bugs in the tests for crowdsourced hinter.

Made tests of the crowdsource hinter module more standardized and easier to read.  Fixed database non-initialization bug in crowdsource hinter module.

Finished prototype of hint moderation view.  Began re-writing tests of the crowdsource hinter module.  (Old tests no longer cover all the code, now that moderation has been added.)