add image explanation

README.md

@@ -35,7 +35,7 @@ Nothing - but please don't leave yet ...
 > -- [Wikipedia - Mau Mau](https://goo.gl/r7D63W)
 
 
-One koan in the [Zen of Python](https://www.python.org/dev/peps/pep-0020/) says: "If the implementation is easy to explain, it may be a good idea". Let's put this to the test and explain the implementation of our Mau Mau program by simply describing the conditions and rules of the game using a rough approximation of the programs' terminology and see if the objects and their interactions make the implementation look obvious. Objects used in the program are marked `like this` ; functions that describe (inter)actions are marked like **this**). The game can also be described in two phases, we could call "setup" and "play".
+One koan in the [Zen of Python](https://www.python.org/dev/peps/pep-0020/) says: "If the implementation is easy to explain, it may be a good idea". Let's put this to the test and explain the implementation of our Mau Mau program by simply describing the conditions and rules of the game using a rough approximation of the programs' terminology and see if the objects and their interactions make the implementation look obvious. Objects used in the program are marked `like this`, functions that describe (inter)actions are marked like **this**). The game can also be described in two phases, we could call "setup" and "play". The image shows all the important elements of the simulation.
 
 ![cardroom overview](docs/cardroom.png)