Hollow polyhedra: Catalan Solids

In two recent posts, thing:16508 and thing:16968, I provided polyhedron openSCAD commands based on the polyhedra libary at netlib.

http://netlib.sandia.gov/polyhedra/

The Catalan bodies were the only convex polyhedra that remained undone in the library and I have now converted them to openSCAD polyhedron commands.

There was one Catalan polyhedron missing from the library, the triakis tetrahedron. To make an openSCAD polyhedron command one needs a set of vertex coordinates and infor