Excluded `examples/pybullet/gym/pybullet_data/` which has many (3000+)
CRLF data files (obj, mtl, urdf), and `docs/pybullet_quickstart_guide`
which has generated .js and .htm files with CRLF line endings too.
this deepmimic is still very slow, due to slow mass matrix/inverse dynamics computation. once spherical motor drive is enabled, it should be fast(er)
move pd_controller_stable to pybullet_utils for easier re-use
add plane_transparent.urdf to pybullet_data
allow spacebar in keyboardEvents (Windows for now)
