Openscad coding techniques

Openscad coding techniques.

First chapter: module
Demonstrating an Openscad coding technique that combines translate, rotate and definition
in a short form, using a "module" definition.

Added a "vectorized" version based on my understanding of a comment from Bikecyclist. Looks more readable.

Second chapter A pre-coded OpenScad input.

For the last complete version, choose: OSCAD-TEMPLATE.scad

You get a pre-coded combination of primitives (cubes, cylinders, cones and spheres), along with the possibility to import an existing STL file. The operations are unions and differences. Intersections are not (yet ?) supported. The parameters are set in a way that nothing happens until you change some of them.

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This is a full code where you just need to change some values to get a result.
You are first in an additive stage, where you can build a part with 2 Openscad "cubes" and 2 cylinders.
In a second