Modified MazeGUI and RoomGUI classes

*Added draw method to Maze and Room classes
These perform the functionality that was originally in their GUI
counterparts. This is so others can continue working with the drawing
portions without having to worry about the construction of the maze.
Eventually, all GUI classes will be removed, and their functionality
moved to their regular counterparts.

*Also, set up a default player name so it is not required to start the
game screen.