Xcode: add glcore.* and remove glew.h

VDrift/vdrift@5206da1
Dependencies: remove GLEW

VDrift/vdrift@f89e178
Xcode: remove car.* from project

VDrift/vdrift@f6b0ed3
Dependencies: update cURL to 7.37.1
Dependencies: update Ogg to 1.3.2
Dependencies: update WebP to 0.4.1
Dependencies: update Boost to 1.56.0
Xcode: fix framework headers not being copied

I have no idea why it defaulted to this when frameworks were added to the Copy Files build phase (Xcode 6.1 6A1027), I can't find any setting in the UI to change it.
Dependencies: revert to Bullet 2.81

VDrift/vdrift#125
Dependencies: update cURL to 7.38.0