fix in b3HashString
remove many unused dependencies from kuka_grasp_block_playback.py (time,math, datetime ,numpy,pylab ,sys, os, fnmatch,argparse were not used!)
move block_grasp_log.bin from Bullet3/data to Bullet3/examples/pybullet/examples/data folder.
PhysicsServerCommandProcessor, derive from CommandProcessorInterface to prepare for different back-end implementation
