Added setup.py to package dudac as a python egg

For the moment dudac has been a developers helper, without being packaged for distribution, this tools has proven to be useful for duda enthusiasts and have it in a suitable form to be packaged and eventually published in [pypi](https://pypi.python.org/pypi) is a good thing.

To create a python package (egg) you can run 'python setup.py sdist'
and a tarball will be left in 'dist/' directory.

The downside is that current users of dudac are using './dudac' to
run the program, with this change they will have to install the egg
or run 'python dudac/main.py'