Guidance: How to work with CrateDB's settings?

## Problem

Because I am not using CrateDB on a daily basis, it took a few seconds longer than needed to come up with this SQL statement to inquire a certain CrateDB setting.
```sql
select settings['gateway']['recover_after_nodes'] from sys.cluster;
```

## Pitch

This is about guidance: If I search for "settings", I would like to receive the best hands-on page to learn about how to work with them, or guided towards such a page quickly.

An excellent option would be that page:
-- https://cratedb.com/docs/crate/reference/en/latest/admin/runtime-config.html

## Rationale

Currently, when searching...

.... all search results aren't bad, because they convey significant portions of CrateDB's settings subsystem.

- https://cratedb.com/docs/guide/install/configure.html
- https://cratedb.com/docs/crate/reference/en/latest/sql/statements/show.html
- https://cratedb.com/docs/crate/reference/en/latest/config/session.html
- https://cratedb.com/docs/crate/reference/en/latest/config/node.html
- https://cratedb.com/docs/crate/reference/en/latest/config/cluster.html

However, none of them answer the question about how to **use them**.

## Solution

Multiple actions should be taken.

a) Cross-link relevant resources.
b) Add excellent [DWIM](https://en.wikipedia.org/wiki/DWIM)-like guidance to the "install/configure" page of the CrateDB Guide, which appears as the first hit.