Customizable coffee mug

=== updated ===
To dive into design with OpenSCAD, I decided to go with a coffee mug, of the cylindrical type. As my first design, it looks pretty good! I am still learning, though. It was made with essentially eight primitives: three toruses and two cylinders, subtracting two cylinders and one torus to make the cavity. My code is a little cluttered, so I will clean it up and perhaps it will render more quickly.

Try setting $fn = 6 and making a hexagonal coffee cup!

Unfortunately,