Decouple objects form SLUICE_ORIGIN
Basic sluice with one level.
Tweak the slice params.
Move receptacles around to match sluice
Restructure sluice code to re-use level, hinge pin and joint creation code.
Add all three sluice levels.
Stagger sluice parts.
Tweak receptacle and sluice positions/geom.
Add a funnel to the roost.
Rework sluice level geometry.
Merge branch 'teeter-totter'