Must clone with submodules

[jmaldon1]

You need to clone with submodules or else python setup.py install will not work.

git clone --recurse-submodules -j8 http://github.com/benjaminjack/python_cpp_example.git

maybe add this to the readme?

[dchapp]

I also had this issue. A note on this should definitely should be added to readme.