Added GameCharacter.

[NEW] Added GameCharacter.
[NEW] Added image and direction attributes to GameObject.
[FIX] Removed Graphics.blur() in SceneTitle which is put wrongly.
Added SpriteCharacter.

[NEW] Added SpriteCharacter.
[NEW] Added update() to SpriteBase.
[ENH] Improved the usage of viewports and sprites.
[MOD] Moved render() from GamePlayer to use sprite.
[DEL] Removed render() from GameObject.