Make construction arrow for renders and use for the Illumination instructions

From #343 (closed) there are different functions for construction lines in the instructions.
Placing a screw, where we want to show the 3D path to the hole the screw goes in:

or placing a part, where we want to show an action:

In the second case an arrow would show the action more clearly

This merge request adds an arrow switch to the construction_line() module in the renders utilities library and uses it in renders for the fitting the illumination module.

It might also be useful in the render for fitting the optics module.

Closes #343 (closed)