Creation of Window and WindowDisplay class
Update of CtS, ConsoleDisplay, Display and Main class

CtS : We added the caracteristics of a window
Main : We changed the selected display to the graphical one
Display : To make the WindowDisplay work we had to update this class to
add some methods
ConsoleDisplay : When we changed the Display class we had to change this
class too

WindowDisplay : This class is the implementation of the Display class to
make a graphical display
Window : This class is the modelization of an Window object