Apple contribution for OSX SSE and iOS NEON optimizations unit tests, thanks to Jordan Hubbard, Ian Ollmann and Hristo Hristov.

For OSX:
cd build
./premake_osx xcode4
for iOS:
cd build
./ios_build.sh
./ios_run.sh

Also integrated the branches/StackAllocation to make it easier to multi-thread collision detection in the near future. It avoids changing the btCollisionObject while performing collision detection.

As this is a large patch, some stuff might be temporarily broken, I'll keep an eye out on issues.

src/BulletDynamics/Dynamics/btRigidBody.h

@@ -494,7 +494,7 @@ public:
 		return (getBroadphaseProxy() != 0);
 	}
 
-	virtual bool checkCollideWithOverride(btCollisionObject* co);
+	virtual bool checkCollideWithOverride(const  btCollisionObject* co) const;
 
 	void addConstraintRef(btTypedConstraint* c);
 	void removeConstraintRef(btTypedConstraint* c);