fix courseware css file so it imports the right files in the right order

Adding script that restarts django when content in the data directories changes.

Courseware css

reading WIKI_ENABLED from env.json

Simplified server restart to just touching lms/__init__.py rather than killing and restarting the server.

Adding an option to watch all extensions; useful for a VIM user where the filesystem events aren't triggered when saving a file without disabling backups.

Problem previewing in the CMS

adding enabled features to aws.py

Eagerly load all modules when reading the course from xml, so that users who are already on a problem page can check their answers