Make setup.py include all packages.

To test:

```bash
mkdir test
cd test
virtualenv my_virtual_env
source my_virtual_env/bin/activate
pip install git+git://github.com/asottile/RefactorLib@6699ed01f18d636577b9baab048fd7089a285b14#egg=refactorlib
python -c 'import refactorlib.cheetah'
```