docs: Add FAQ and sponsors to README (#20)

fixes #19

README.md

@@ -114,6 +114,34 @@ export default [
 -   `no-duplicate-keys` - warns when there are two keys in an object with the same text.
 -   `no-empty-keys` - warns when there is a key in an object that is an empty string or contains only whitespace (note: `package-lock.json` uses empty keys intentionally)
 
+## Frequently Asked Questions
+
+### How does this relate to `eslint-plugin-json` and `eslint-plugin-jsonc`?
+
+This plugin implements JSON parsing for ESLint using the language plugins API, which is the official way of supporting non-JavaScript languages in ESLint. This differs from the other plugins:
+
+-   `eslint-plugin-json` uses a processor to parse the JSON, meaning it doesn't create an AST and you can't write custom rules for it.
+-   `eslint-plugin-jsonc` uses a parser that still goes through the JavaScript linting functionality and requires several rules to disallow valid JavaScript syntax that is invalid in JSON.
+
+As such, this plugin is more robust and faster than the others. You can write your own custom rules when using the languages in this plugin, too.
+
+### What about missing rules that are available in `eslint-plugin-json` and `eslint-plugin-jsonc`?
+
+Most of the rules in `eslint-plugin-json` are actually syntax errors that are caught automatically by the parser used in this plugin.
+
+Similarly, many of the rules in `eslint-plugin-jsonc` specifically disallow valid JavaScript syntax that is invalid in the context of JSON. These are also automatically caught by the parser in this plugin.
+
+Any other rules that catch potential problems in JSON are welcome to be implemented. You can [open an issue](https://github.com/eslint/json/issues/new/choose) to propose a new rule.
+
 ## License
 
 Apache 2.0
+
+## Sponsors
+
+<!-- NOTE: This section is autogenerated. Do not manually edit.-->
+<!--sponsorsstart-->
+<!--sponsorsend-->
+
+<!--techsponsorsstart-->
+<!--techsponsorsend-->