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).

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