Improve documentation for the "Use jsonapi_include query in url" setting

Problem/Motivation

Currently it's unclear what's the case when the "Use jsonapi_include query in url" is disabled (the default).

It seems in that case all includes are automatically run through the enhancements?
This should be explained and perhaps the option should be implemented vice-versa, enabled by default, something like "Automatically apply inclusion to all requests"?

Steps to reproduce

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes