Fix forward slashes in index for win32 resources
Fix forward slashes in index for win32 resources

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