Add strap mounts on sides.
Add support for test prints.
Close bottom front for stability.
Ignore generated files.
Add comments.
Modify the strap holders for comfort.

The straight up version of the strap holder fit a little tight against
the temples. This version has them lean outward about 5 degrees on each
side. Hopefully this is more comfortable.
Simplest attachment method.

Provide little nubs to run elastic bands around.
Restructure the scad files.

Separating major components of the code into separate scad files to
simplify making different variants without a whole lot of conditionals.

The main body deserves it's own component.
The phone mount will change, so it has it's own component.
Added a main file that brings together components.

Also renamed "viewer" to "visor". Better term.
Modify test variant for mount test.

Modified the "test" variant so that I'm only printing the front part
of the visor. This exposes the elastic mount points for testing without
requiring the whole visor.
Tweak cooling parameters for better adhesion.
Comments and cleanup.
Improve elastic mount printability.

The mount points failed in terms of the look of the print. Structurally,
they did pretty well.

Hopefully these changes and the cooling changes in config.ini will
result in a better print.
Reduce dependence on globals.

Modified several modules to take parameters instead of depending on the
global values. Added more documentation for the new parameters.