Added Features and Bug Fixes

-Add a new main menu screen.
-Added multiplayer mode.  See ReadMe.txt for controls.
-Updated ReadMe.txt with controls.
-Added new backgrounds for game modes.
-Added a logo sprite for the main menu.
-Added new sprites for main menu buttons.
-Updated various graphics loading methods.  Main update was to loading
the second player's graphics.  copySprite method needs to be reworked
due to memory clearing issues that occur later.
-Removed updateUserData in generic.c due to issues with certain
emulators.
-Updated comments a bit more in some sections of the code.
-Recompiled with latest build.