Make a parameterization concept

In this step, we want to make the Lego brick part fully parametric and reusable. Via using parameters, we want to:

• control the number of knobs in both directions

• control the brick's height

• create a reusable Lego brick library so that we can write this:

  lego_brick::LegoBrick(rows = 2, columns = 2, base_height = 9.6mm * 2);
  

• All our sketches shall lay beside that LegoBrick inside a new module lego_brick.

First, though, we need to find a way to place elements more generically than before.