Issue 326: zombie scheduled items still called if already queued inside tick() method (fixed).
Issue 326: zombie scheduled items still called if already queued inside tick()
method (fixed).

adamlwgriffiths/Pyglet,niklaskorz/pyglet,adamlwgriffiths/Pyglet,seeminglee/pyglet64,niklaskorz/pyglet,seeminglee/pyglet64,niklaskorz/pyglet,adamlwgriffiths/Pyglet,niklaskorz/pyglet,adamlwgriffiths/Pyglet,seeminglee/pyglet64