Convert to using arbors.
Convert to using arbors.

git-svn-id: http://svn.code.sf.net/p/petavision/code/sandbox@2257 7c0444ca-5550-0410-9008-faecdbe78eb5

Former-commit-id: d2220fe6b4275763e6539112e6d5833d5f2eea7e
dpaiton/OpenPV,dpaiton/OpenPV,dpaiton/OpenPV,PetaVision/OpenPV,dpaiton/OpenPV,dpaiton/OpenPV,PetaVision/OpenPV,PetaVision/OpenPV,dpaiton/OpenPV,PetaVision/OpenPV,dpaiton/OpenPV,dpaiton/OpenPV,PetaVision/OpenPV