Parametric license plate generator

I needed a name license plate for a photo shoot and realized there's not a good one to be found … so here it is. Also works for placing on your dashboard, trucker style!

Made in OpenSCAD, requires [the great BOSL2 library](https://github.com/BelfrySCAD/BOSL2/).

Plate parameters:

- `plate_width`, `plate_height` and `plate_thickness` are the plate dimensions
- `border` set to 1 if you want the raised border, set to 0 if not.

Magnets:

- `generate_magnets` if you want magnet holes, set it to 1; 0 otherwise
- `magnet_width`, `magnet_height` are the magnet size (same parameter for circle or square magnets)
- `magnet_type` is 1 for round magnets, 0 for square magnets
- `magnet_number` is how many magnets to place on a row
- `tolerance` is 0.1 mm by default, to avoid having to push the magnets too hard

Text:

- `text_font` is the typeface; EU license plate font is DIN 1451 Mittelschrift, get it from here for example
- `text_size` defaults to 0.66 of the plate height
- `text_height` is th