Cleanup testing code

[borntyping]

1. [x] Use url_for instead of urls and format strings
2. [x] Write convenience methods for self.client.get(url_for(endpoint, ...)) These should use current_app so that they don't have to be attached to anything.
3. [ ] Cleanup the test framework classes - split up Flask app testing and Tentd testing like I did before.
4. [x] Try and make the code a bit more standard and easier to read - possibly use nose and assert instead of the unittest modules methods

[borntyping]

py.test would actually make a lot of the stuff the tests do easier.

It would also provide monkeypatching, so we could drop mock.

[borntyping]

Once this is finished, I should remove the arguments passed to py.test in setup.py