authors: team-810
Button functions finalized, ready for debugging.
Left button: move left 1 unit with a 10 ms delay; can move while jumping or falling; should not move when hitting a wall.
Right button: move right 1 unit with a 10 ms delay; can move while jumping or falling; should not move when hitting a wall.
Jump button: jump to as high as 100 unit at most; move up 1 unit with a 10 ms delay; cannot jump while falling.
Early release of the jump button causes the character to fall. Falling is 1 unit down with a 10 ms delay.
Falling should occur even if no button is pressed. Should not fall below the ground.
Current setting: ground level: 0, left wall: -1000, right wall: 1000.
Drawing functions finished. Added a goal function and another layer of ground.
Added starting and ending screens
Changed movement so that there is 'no' delay
Changed jump height so that the user will be able to jump as high as 60 units at most