Add a tutorial for the frustum_visual example

[iche033]

A FrustumVisual class was added in #1095 for visualizing the frustum of camera sensors. An example exists in examples/frustum_visual. We should add a tutorial explaining the example, very much like other tutorials in the tutorials dir.

Implementation suggestion

1. Add a frustum visual tutorial in the tutorials directory
2. In the tutorial, provide steps for building the example, and the expected output (screenshot).
3. Add explanations for the code, specifically for the API calls needed to construct a FrustumVisual.
4. Once done, the tutorial needs to be added to tutorials.md.in

See other tutorials in the tutorials directory for reference. These tutorials should be fairly straightforwad.

[SuperGops7]

Hi @iche033 , I'd love to work on this. Can this be assigned to me?

[ahcorde]

Hi @SuperGops7

I assigned the issue. Feel free to include here the PR