Cleaning Code and Delegating Functions

Made parts of draw() additional functions like SnakeMovement() and
BulletMovement(). Moved code from foodPellet() constructor to
newFoodPellet() to SnakeHunter, that would make randomly generated x and
y coordinates reachable to the snake, and should properly have been
there. Made code more readable, especially for functions checkBullet and
checkForSnakes. Also made 'a' and 'd' work as keys to move the gun.