Adding a pip install?

[ardunn]

Hi,

Would any of the developers be interested in making cgcnn pip-installable (instead of conda) and publishing CGCNN to PyPi (.e.g, pip install cgcnn)? I ask because:

• many people (myself included) want to use CGCNN but don't use conda
• to install CGCNN without pip or conda requires manually adding CGCNN's path to PYTHONPATH so it is importable

This PR is a first step in that direction, if anyone is interested.

Thanks!