Created new interface for game portions

The classes that will implement this represent portions of the game,
such as
*Intro Screen (new game, load game, etc)
*New Game (choose player name, difficulty)
*Game itself
*Game Over

This interface allows ease of control in the new GameDriver,
and provides a known close method for clean up.
Created basic IntroductionGUI class

This class will show a GUI that can be used to either
-Start a new game
-Load a saved game
-Get help

Very basic form right now.
Created basic NewGameGUI class

This class will display a GUI that allows the user
to enter his/her name and choose the difficulty level.

Very basic form right now.
Fixed drawing in GameGUI, added interface

*Fixed the drawing in GameGUI - before it would not always redraw the
maze

*Made GameGUI draw the maze as soon as it is created.

*Made GameGUI implement the GamePortion interface and added the close
method
Added GameDriver class to transition game portion

Created new GameDriver class. This class will control the transitioning
between game introduction, new game, game itself and game over.

For now, only game introduction, new game, and game itself are
implemented.