:neutral_face: Use py.test to run tests

PS - there aren't any at the moment :)
:neutral_face: Add example unit test
:grin: Add example integration test

This one uses the django_db mark to allow database access within the
test.
:grinning: Add example functional test using Django client

To provide something to test against, we include a dummy homepage.

This fixture is provide by django-pytest so this is easy.
:smile: Add example functional test using webtest

I adopted an existing fixture for this.
:heart_eyes: Add example functional test using webdriver

Now this was *way* easier than I thought it was going to be. It's pretty
trivial to add a firefox fixture and use it in your tests.
Add example functional test using splinter
Purge nose
Add py.test coverage plugin to requirements
Merge pull request #24 from tangentlabs/i-♥-py.test

Learning to love py.test