vrevent.py: add a Tiltbrush-style drawing example using pybullet Expose getVREvents to pybullet / shared memory API, access to any VR controller state & state changes. Improve performance of user debug lines (pybullet/shared memory API) by batching lines with same color/width expose rayTest to pybullet/shared memory API (single ray for now) add pybullet getMatrixFromQuaterion