Docs: Add missing info about special status of home-dir config files. (#9472)

This seems to be the last step in liquidating issue #7729.

Author: jrpool

docs/user-guide/configuring.md

@@ -3,7 +3,9 @@
 ESLint is designed to be completely configurable, meaning you can turn off every rule and run only with basic syntax validation, or mix and match the bundled rules and your custom rules to make ESLint perfect for your project. There are two primary ways to configure ESLint:
 
 1. **Configuration Comments** - use JavaScript comments to embed configuration information directly into a file.
-1. **Configuration Files** - use a JavaScript, JSON or YAML file to specify configuration information for an entire directory and all of its subdirectories. This can be in the form of an [.eslintrc.*](#configuration-file-formats) file or an `eslintConfig` field in a [`package.json`](https://docs.npmjs.com/files/package.json) file, both of which ESLint will look for and read automatically, or you can specify a configuration file on the [command line](command-line-interface).
+1. **Configuration Files** - use a JavaScript, JSON or YAML file to specify configuration information for an entire directory (other than your home directory) and all of its subdirectories. This can be in the form of an [.eslintrc.*](#configuration-file-formats) file or an `eslintConfig` field in a [`package.json`](https://docs.npmjs.com/files/package.json) file, both of which ESLint will look for and read automatically, or you can specify a configuration file on the [command line](command-line-interface).
+
+    If you have a configuration file in your home directory (generally `~/`), ESLint uses it **only** if ESLint cannot find any other configuration file.
 
 There are several pieces of information that can be configured: