Various optimzations to physical packing to improve speed
Merge branch 'new-simulator' into physical-packing-faster

* new-simulator:
  Updated simulator to latest version
Additional algorithmic improvements to physical packing.  Tuning of the physical packing parameters to improve speed and results
Simple efficiency improvement for jiggling
Merge pull request #22 from adamreis/physical-packing-faster

Faster physical packing and jiggling