experimental/animation.py: Fix frame.delay reference, which was renamed to   frame.duration in AnimationFrame in r6ddcd54890a1. Add meaningful version.
experimental/animation.py: Fix frame.delay reference, which was renamed to
  frame.duration in AnimationFrame in r6ddcd54890a1. Add meaningful version.

niklaskorz/pyglet,niklaskorz/pyglet,niklaskorz/pyglet,adamlwgriffiths/Pyglet,adamlwgriffiths/Pyglet,adamlwgriffiths/Pyglet,adamlwgriffiths/Pyglet,niklaskorz/pyglet