Install via Setuptools

You can run `python setup.py sdist` to build a .tar.gz file, and then `pip install dist/camcrypt-1.2.0.tar.gz` to install it.

It is this camcrypt-1.2.0.tar.gz file that would get put on PyPI so you can install from anywhere with `pip install camcrypt`.

Usage should be exactly the same, except you don't need to pass it a library path (by default it selects the one built and included with the package). I can also update the README with more directions.