Update to py.test
removing expect
removing expect -- not complete
removing expect, incomplete
tests pass
work in progress with a crap-ton of failures
support for GitHubError
tests pass
Add unittest 2 && pin dependencies
Use `python setup.py test` to run tests

- Let setup.py determine what we actually need to run the tests, i.e., on
  python3 we won't need unittest2 and requirements.txt is too stupid to know
  how to manage that.
tests pass
tests pass
tests pass
not using it, doesn't need to be imported
tests pass
tests pass
tests pass
tests pass
Added test for `authorize` without `scopes`
Optional-ised `Github.authorize` scope argument