Django sass process 622

[groovecoder]

I'm happy to wait on this, but I wanted to put it up here for consideration ...

This includes #625 and adds django-sass-processor so we can just keep .scss files in the repo, and let django-sass-processor compile the .css files during deployment release.

The alternative to this is either:

1. Check the compiled .css files into the repo and hope we don't forget them each time
2. Use Heroku Buildpack Multi to compile the .scss files into .css with Ruby sass command

[groovecoder]

sass_src automatically converts this to look for the compiled .css file.

[coveralls]

Coverage increased (+0.004%) to 90.197% when pulling e1a3fce on django-sass-process-622 into 8d556ac on master.

[maxxcrawford]

What is the development process when you're working on local changes with the Django tool? Do we still leave the README the same for now, or reference the offline compile option from the Django-sass-processor documentation?

[groovecoder]

As I understand it, django-sass-processor automatically compiles the .sass into the .css every time it's included in a template. So the local development process is just to save the .sass file and reload the page.

This PR also adds a new release-tasks.sh script for heroku to run python manage.py compilescss after it runs the db migrations. So during the stage & production deploys, we compile the sass "offline".

[maxxcrawford]

10-4. This is good by me!