Lots of simple test data
small correction to ZMP (appears that angular vel/mom/mom' vectors are
inverted. This was not true, but was caused by a swap from right-handed
to left-handed coordinate system: it was assumed that only the z and y
axis where swaped when compared to that in the ZMP paper, but to
preserve right-handedness we must swap (paper -> my code): z -> y, y ->
x, x -> y)