cleaned up some of the arbiter code using the constraint/util.h helper functions
cleaned up some of the arbiter code using the constraint/util.h helper functions

git-svn-id: d9d6db7128765a3d84cbcddf81cbe31dc48065ee@148 f928779d-404e-0410-9e50-157fa1f9005b

Plingot/Chipmunk-iOS-framework,Plingot/Chipmunk-iOS-framework,Plingot/Chipmunk-iOS-framework