cube: respect start_from_point
cube: respect start_from_point

jpinedaf/pyspeckit,e-koch/pyspeckit,jpinedaf/pyspeckit,keflavich/pyspeckit,vlas-sokolov/pyspeckit,keflavich/pyspeckit,e-koch/pyspeckit,pyspeckit/pyspeckit,pyspeckit/pyspeckit,vlas-sokolov/pyspeckit,low-sky/pyspeckit,low-sky/pyspeckit