Added usage hint to Sprite.  Seems to have a slight improvement on framerate on Astraea, but hard to tell.  LOS test, someone?
Added usage hint to Sprite.  Seems to have a slight improvement on framerate
on Astraea, but hard to tell.  LOS test, someone?

mammadori/pyglet,theblacklion/pyglet,theblacklion/pyglet,theblacklion/pyglet,oktayacikalin/pyglet,theblacklion/pyglet,oktayacikalin/pyglet,oktayacikalin/pyglet,oktayacikalin/pyglet,mammadori/pyglet,mammadori/pyglet,theblacklion/pyglet,oktayacikalin/pyglet,mammadori/pyglet