Blender Git Loki

Testing commit for OS X trackpad and scroll events.

Now:
- code is wrapped for OS X releases (10.6 and 10.7)
- It now detects scrollwheel (old mouse) and gesture strokes (mighty mouse or trackpad).

If you have 10.6, things will work as for release.

Next todo for tomorrow: make trackpad work actually smooth and not with steps.
Will also try to figure out the device type, to handle mighty mouse differently.