Added Sphinx documentation to create a website for the Virtual Machine.

I added directory `doc` which sets up everything to generate html documentation for the Virtual Machine. The idea is to create a website which serves as a general landing page for users where all the information comes together.

I put a built of the documentation at http://heistermann.github.io - please check it out!

If the Pull Request was approved at some point, we could host the website under http://openradar.github.io - then I'll delete http://heistermann.github.io, of course.

If you want to build the documentation yourself, make sure you have Sphinx installed. Then go into the `doc` directory and execute `make html`.

Bests,
Maik