Add fitted nodes in after corners and polygon nodes since the fitted nodes
are less important. Subsequent nodes will "snap" to previous nodes if
they are "close enough."
Need to manually divide segments to prevent "T" intersetions which can
confound the triangulator. Hey, I got to use a recursive method!
Pass along correct triangle attributes to output file generator.
Do fine grained node snapping for corners and polygons, but course grain
node snapping for fitted terrain nodes.
