Added Math::Scale()

-Takes a Vector2f and a scale factor
-Returns a new Vector2f with x and y values of the Vector2f mulitpled
with the factor
-Does not modify the Vector2f.
Added FlipAndScale()

-Takes a Vector2f, a factor and the height of the object.
-Scales the Vector2f using Math::Scale() and then subtracts height from
the Vector2f's y value
-Returns the Vector2f
Changed rendering

-Renamed UpdateGUI() to RenderMainText()
-Removed RenderEndGame() and RenderInGame()
-Combined RenderEndGame() and RenderInGame() into RenderMainText()
-RenderMainText() now handles rendeinrg of main text except when Player
gets a bonus effect.
-Reduced calls to UpdateGUI()/RenderMainText().
-Renderer::RenderPoints()/RenderBallCount()/RendererLives() are now
updated when this property actually chnges ( Player hits a Tile, Player looses a Ball, etc... )