share more data structures and code between OpenCL and C/C++ on CPU:
move the setConstraint4/b3ConvertConstraint4 to shared code.
share more data structures and code between OpenCL kernels and C/C++ code on CPU (non-OpenCL)
integrateSingleTransform
fix bug in registerRigidBody (could lead to random crashes, especially when performing picking/adding rigid bodies afterwards)