Psychopy OSX 64-bit compatibility added

Got psychopy to work on 64-bit OSX systems, with the latest snapshot of pyglet 1.2 alpha 1 from code.google.com (190c95ab345e)
I mainly omitted some code blocks that prevented psychopy from finding pyglet or which caused segmentation faults. I don't know how crucial these blocks are for correct functioning of psychopy, but after disabling them all demos ran fine for me.

The three main changes were:
- Disabled overloading of pyglet.lib. This caused pyglet.gl (specifically gl_info) to not be found anymore afterwards. To my understanding this is only to aid in finding avbin, but if you do not use this, one can skip this step.
- Changed
    self._hw_handle=self.winHandle._window.value
to
    self._hw_handle=self.winHandle._nswindow  
though I have the feeling this is not entirely correct here. _window.value pointed to the window ID of the pyglet window, but ._nswindow points to the complete objc reference of this window. I couldn't find the window id value in this structure. Nevertheless, this change did the trick and I have no idea if the window ID value will ever be used somewhere else by psychopy?
- Disabled platform_specific.syncSwapBuffers(1)
somehow this caused a segmentation fault and crashed everything...