Structure to be able to install with pip, publish on pypi

I was about to have to write this code myself, then found your repo and was so happy I wanted to use it right away. But to be able to add your code as an external dependency, I had to be able to install it using the pip package manager. So here is the basic structure that's needed to be able to do:
```
$ pip install git+https://github.com/martinmelin/python-image-orientation-patch.git@prepare-package
```

The URL will of course be ```git+https://github.com/kylefox/python-image-orientation-patch.git``` when this is merged into master.

If you want, it should be very easy to publish this on https://pypi.python.org now. http://www.scotttorborg.com/python-packaging/minimal.html#publishing-on-pypi is a good guide on how to do it. The only thing that needs to be updated is to pick a license and set it in ```setup.py```.

Thanks for your code!