in jigsaw, addresses higher order polynomials (and polynomials over a constant...

in jigsaw, addresses higher order polynomials (and polynomials over a constant hermite spline) for spacecraft position, fixes #783

git-svn-id: http://subversion.wr.usgs.gov/repos/prog/isis3/trunk@4723 41f8697f-d340-4b68-9986-7bafba869bb8