Make high joint relative to local coords.
Restructure to use separate bodies for each element.
Get the hinge tracks working.
Add dampened spring effect to slides.
Adjust sluice geom downward.
Remove prismatic hinge track.
Restructure creation of parts into loops.
Enable picking of the sluice hinge.
Rename level -> lever
Make the sluice level slidable.
Add opt_ovality to the egg ctor.
Randomize the ovality of the eggs.
Merge branch 'teeter-totter'