Thoughts from a newb on the getting started documentation

[sdfgeoff]

I have been starting to use Rapier for a project, and thought I would write down some of the sticking-points regarding the getting started guide. I am something of a newbie at rust and at physics engines, so feel free to close this issue if you think it is off-topic or if I am being to noobish.

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The rust user guide for how to use bevy ends with the main loops being:

loop {
        pipeline.step(
            &gravity,
            &integration_parameters,
            &mut broad_phase,
            &mut narrow_phase,
            &mut bodies,
            &mut colliders,
            &mut joints,
            &mut ccd_solver,
            &physics_hooks,
            &event_handler
        );
    }

for all the demos.

As a new user of rapier, I was initially confused how to get information back out of the engine (aka what do I do with a body handle). Perhaps extending the first example with:

println!(bodies.get(body_handle).position())

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I initially found attaching collision shapes to rigid bodies fairly confusing: To me a CollisionSet was a just set of collision shapes - the same as the RigidBodySet is just a set of rigid bodies. This isn't helped by the getting started guide stating

A collider set is a container that maps a unique handle to a collider:

Perhaps a simple change to:

A collider set is a container that maps a unique handle to a collider and maps colliders to rigid bodies

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Do you think it is worth me creating a PR with these changes?

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Side note, why does every rust project have a bunch of documentation outside cargo-doc? It means I have to learn dozens of different static site generators to make PR's on them, and it's out-of-sync with the codebase, not auto-tested etc. etc.
Have you considering moving the pure-rust documentation into the crates module-level docs? There is a lot of stuff that can be directly copy-pasted from one to the other. Is it worth creating a bunch of PR's on the main Rapier repo doing this?