Distutils-ability

Hi,

I've fixed one syntax error in listen.py, and I've created a first crack at a distutils setup.py file- which will let you install this as a library. I've also gone ahead and fixed the #!/usr/bin/python3 statements to #!/usr/bin/env pthon3, which will allow the software to work on more platforms, and inside a venv.

- Serge