Is this the default setting for `BROKER_URL`? Even so, we should ask the user to input this setting by overriding the `ask` method.

Also, from http://docs.celeryproject.org/en/latest/django/first-steps-with-django.html looks like we'll need to add

    import djcelery
    djcelery.setup_loader()

to settings, but right now we don't support custom code in `settings.py`

https://github.com/agiliq/mason/blob/master/mason/templates/default/project_name/settings.py#L176

Will need to think how to implement this.