Walk1.2

Polished idle -> walk -> idle transition. Generally improved transitions (added 'reach poses', smoothed motion)

The audio (footstep sounds) are disabled by default, as they cause noticeable glitches in the motion - for clear explanation of the problem and documentation of solutions already attempted, please see: https://www.youtube.com/watch?v=jlibGTBCtCU
We should be using joint names, not offset numbers to group them.   Why do we need to do this?