don't need indexing for toKiteProto anymore
homotopy forces/torques are now algebraic variables, not controls
add code to replay optimization movies in fast motion, or animate a flight path
plotter: now Seqs have [] around the names, and Maybes have ()
outputs which are numpy 0-d arrays are now converted to scalars
constraints and bounds feedback can now output a string
trajectory interpolation will now never extrapolate by accident