Added Issues (#16 -21), Fixed Issues 16, 18, 20 and Updated README.md

Project 2 Pacman Project Submission

Added Issues: 
#16- Fix JUnit Tests, because tests were not compiling. And later, some of the tests were failing.

#17- Refactor Leaderboard and LeaderboardGUI interaction - We felt that the organization of the LeaderboardGUI containing a Leaderboard instance was not ideal for adaptability if new GUI's were added.

#18- Change Default Pacman Movement Controls - The default controls were the WASD keys which was illogical since pacman is the main character and you don't need to use the mouse to interact with the game,

#19- Comment the Complicated Functions - While working on the project, we found many complicated and confusing functions that took many hours just to understand (some we still don't understand), and so it would be very helpful for future CS56 students if these were commented in detail.

#20- Improve Leaderboard Graphics - Originally when we created the LeaderboardGUI we were focusing on functionality, not appearance, so the graphics were very simple and not appealing.

#21- Making screen larger - When playing we felt that the screen of the game was too small.

Requested Points = 50 points/issue ~ 300 Points

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Fixed Issues:

#16 - (See Above For Details)
    Requesting ~ 50 Points

#18 - We changed Pacman controls to be the arrow keys, MsPacman's controls to be WASD  (when in two player mode), and then had the ghosts have WASD and Numpad 8546 controls during the 'versus' mode of the game (See above for more details).
    Requesting ~ 25 Points

#20 - We improved the appearance by centering text, displaying the user's score, adding a Pacman image, and changing colors to be more pleasing. We also added a "Play Again" button that goes back to the game and allows the user to continue playing.
    Requesting ~ 150 Points

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Updated README.md -- We improved the general game description, added a screenshot of the home screen, updated the controls, added internal documentation (for future contributors), and added running instructions.  
    Requesting ~ 100 Points