Create structured docs in the Wiki #46

At the moment all the SolidPython documentation is in the README (and the examples).

It would be nice to use the wiki to gather all docs and create a central, browsable documentation page for SolidPython. As reference, the BOSL2 wiki is pretty handy for me and I'd like to have something similar for SolidPython.

I started adding pages to the wiki and want to extract several parts from the readme into the wiki.

Any help -- especially in form of wiki pages covering what ever you think is important -- is welcome!