Commit so I can merge with changes from Chris.
Merge branch 'master' of https://github.com/chrisvandergeer/MonopolyCasus.git
Added AI interface and abstract class and created 2 different AI classes.
RiskyStraatkopendePlayerIntelligence and VoorzichtigeHuisjesMelkendePlayerIntelligence
Now the AI behaviour get inserted into the player via the contructor.
Hence all the little changes in the various unittests