Added loading of config file with room data.

Rooms are now loaded from data/config/rooms.json. Starting room can also be
specified. Ideally we should have a separate IO-system and an intermediate data
format between IO and model...
Also added a couple of libraries that we will need. Those using Eclipse will have
to add the .jar's to the project.
Merge branch 'development' of https://github.com/jrrr/Sten into development

Conflicts:
	sten/src/sten/model/Room.java