Models are extraneous for something as temporary as a notifaction -- this change
moves all the configuration into the views, and removes the models entirely.

Rather than directly invoke command-line Python (and Mako) from the
assets Rakefile, or call an external Python script, use a Django
management command to preprocess all asset template files.

An "asset template file" is defined as a static asset file with a
file extension indicating that it needs to be run through a template
engine prior to Sass/CoffeeScript compilation or packaging with other
assets. The preprocess_assets management command will look through
all of the files listed in the `STATICFILES_DIRS`, preprocessing each
as needed. Preprocessing strips off the special template file
extension, creating a new file in the process.

Currently, the only variable accessible in an asset template file is
the `THEME_NAME`, defined in the settings.

Use MITX_FEATURES to tell if we're in the CMS; this is much cleaner. Also use $.data instead of a hidden div.

PREVIEW_LMS_BASE must now be set (default value does not work for both edge and edx). Make this work locally as well.
https://edx.lighthouseapp.com/projects/102637/tickets/331

This reverts commit e13556b8b6b54b2791fe7bb1ba2ae5cde10114ce. This is because the
JS files need to be loaded in a specific order for the tests to run properly, and
we don't yet have a way to declare that.

Hacking the Python, because our JS dependency management is borked.

Start linting envs files, add task to only pylint errors, and move pylintrc file to the correct location

while looking for it

This allows us to a) compile the coffeescript and sass from xmodules
using the new out-of-band method and b) reload xmodule static content
whenever it changes, which should make devs much happier.