Update the documentation with platforms requirements (#37)

This is for issue#37, I updated the requirements we need to have on client/slave nodes in order to be able to run tps testruns.
@whimboo can you review this?
Instead of putting all that into our own readme, can't we link to necessary requirement pages for the different modules in use? Thing is that I don't want to update our pages all the time, dependencies are getting changed.