Create a proper python installer

[Kristian Evers]

Make a setup.py that uses python's setuptools. Ideally we want to get rid of the current build script and let setuptools build the code instead. This way it will be easier to distribute the package on PyPI.

We need to install dhmqc as a python package that can be compiled via setup.py. A command line app is also needed for this to make any sense. This way we can make a CLI that does something like:

dhmqc coverage *.las coverage.sqlite

and

dhmqc dem_gen coverage.sqlite jobdef.json