attempting to merge my 1.7-friendly updates

Hi arne,

Made changes here to allow it to run under django 1.7. A  bunch of it just ends up being whitespace cruft (sorry).

Actual changes:
* using django.utils.timezone  instead of datetime from the standard library
* changed import from django.conf.urls in urls.py to be 1.7-compliant

All the tests now pass and I have a basic test app working.

I think we're going to be using this in production under 1.7 at The Dallas Morning News labs team, so if you'd like any help maintaining it, I'd love to pitch it with patches, documentation, whatever.

-D