screw extrusion lib for polyhedron

When it comes to threads, most people's approach is a for()-loop with many segments, that consist of `hull(){shape(n); shape(n+1)}` or a set of simple polyhedrons. This takes long to render and has it's restrictions due to the early passing of work to openSCAD.
As an alternative to that I have written the function `screw_extrude_v()`, that returns the required parameters for `polyhedron()`.
Besides the standard-parameters for such functionality it receives a vector with the points of a a poly