Add setup.py python build script.

This setup.py builds and installs the python bindings, shared library, and command line program.
It would be great to read this from `src/ybinlogp/__init__.py`.  

```python
about = {}
with open('src/ybinlogp/__init__.py',) as f:
    exec(f.read(), about)

...
    version=about['__version__'],
```

I think something like this should work.