Remove TEST_RUNNER setting

Running ``manage.py test`` was throwing "ImportError: No module named
discover_runner."

The Django 1.7 docs say: "By default, TEST_RUNNER points to
'django.test.runner.DiscoverRunner'"
Merge pull request #47 from jwalgran/topic/remove-test-runner-setting

Remove TEST_RUNNER setting
Set up CRLF handling for Windows clients
Create Django apps with models, URLs, and view stubs

* Keep `core` app small (with no UI, and just the ubiquitous User and Group models)
* Create topic-specific apps for handling groups of models and the URLs that service them
* Name all URLs (usually the view name)
* Use a `urls` module where an app handles URLs with more than one prefix
* Create view stubs for all URLs and import where referenced
* Create stubs for decorators and import where referenced
* Add apps to `settings.LOCAL_APPS`
* Distribute all models from `doc/draft-models.py` and all URLs from `doc/draft-urls.py`

Note that it all loads in our `app` VM using this command:
     envdir /etc/nyc-trees.d/env ./manage.py shell
squash me
Include Pillow in Django requirements