Missing features for Sprites

[DarthGandalf]

• [ ] Animation speed: e.g. the two balls (health/mana) have 24 and 20 frames per second, to avoid being in sync.
• [ ] Partially render the sprite: the ball's image is just a ball, but when the health or mana is not full, only part of it should be drawn
• [ ] Change color: mana is blue, poison is green, but the image is the same, and it's red. HD images do color changes in HSV space.