Problem/Motivation
There is no complete documentation for the creation and editing of the settings.php and settings.*.php files. The comments in the files themselves has worked to date, but we can do better.
Proposed Resolution
Create and maintain a documentation page on Drupal.org with this information. Using the module and theme .info file documentation pages (https://www.drupal.org/docs/8/creating-custom-modules/let-drupal-8-know-... and https://www.drupal.org/docs/8/theming-drupal-8/defining-a-theme-with-an-...) as examples to help get thing started.
Remaining Tasks
- Determine if this documentation is best as a sub-guide or a page
- Determine which existing documentation guide this should be part of
- Determine sections of guide/page (appropriate groupings of settings)
- Identify existing related documentation
- Convert existing content from default.settings.php and example.settings.local.php