Add first prototype for a loft() module.
Fix polygon orientation.
Add scaling and rotation.
Add path extrusion and move the code to a separate file.
Handle child nodes and update shape transformation to handle most path.

There are still some cases that do not produce the intended output, e.g.
a circle around the x axis flips the shape when crossing the x/y plane.
Fix build.
Handle path connection.
Create rotation matrices incrementally.

This is based on the OpenSCAD code posted on the OpenSCAD forum by Oskar
(http://forum.openscad.org/slow-render-td6556.html).
Change scale and offset to use a single function.
Rebase to unstable branch.