small changes

I went over the thing again, but I don't see a good way to get neutral handling much better, without switching the cone space we're using. I double-checked the equations and it all looks sensible to me.

I fixed up the comments a bit and added (another) cli version. I did a nip2 version too, screenshot here:

  http://www.rollthepotato.net/~john/dalton.png

you can edit the matrices and watch the effects, which is quite nice.