Rename *_RECIP settings to *_TO for consistency
Fix test generators and run pep8/pylint

- Nosetests doesn't handle test generators well if they're class methods
  or decorated (say, with @patch). I moved all the tests to functions,
  and fixed the parts that weren't passing

- Made a bunch of pep8/pylint fixes.

- Split the two test classes from tests/test_server.py into test_server
  and test_customization