Add improved docs

Author: wooorm

readme.md

@@ -8,20 +8,43 @@
 [![Backers][backers-badge]][collective]
 [![Chat][chat-badge]][chat]
 
-**[xast][]** utility to build a [`sitemap.xml`][sitemap].
-Supports localization as suggested by [Google][].
+[xast][] utility to build a [`sitemap.xml`][sitemap].
+
+## Contents
+
+*   [What is this?](#what-is-this)
+*   [When should I use this?](#when-should-i-use-this)
+*   [Install](#install)
+*   [Use](#use)
+*   [API](#api)
+    *   [`sitemap(data)`](#sitemapdata)
+    *   [`Entry`](#entry)
+*   [Types](#types)
+*   [Compatibility](#compatibility)
+*   [Security](#security)
+*   [Related](#related)
+*   [Contribute](#contribute)
+*   [License](#license)
+
+## What is this?
+
+This package helps you build a [`sitemap.xml`][sitemap].
+It supports localization as suggested by [Google][].
+
+## When should I use this?
 
 This package focusses on a small set of widely used parts of sitemaps.
 It has a few good options instead of overwhelming with everything that *could*
 be done.
 If you do need more things, well: this utility gives you a syntax tree, which
 you can change.
 
-Intended for sites with up to 50k URLs and a resulting serialized contents of
-up to 50MB.
+This proejct is intended for sites with up to 50k URLs and a resulting
+serialized contents of up to 50MB.
 Wrapping this project into something that generates sitemap index files is left
 as an exercise to the reader.
 
+You don’t always need a sitemap.
 [See Google’s recommendations for whether you need a
 sitemap](https://developers.google.com/search/docs/advanced/sitemaps/overview)
 
@@ -32,18 +55,28 @@ sitemap changes to Google.
 
 ## Install
 
-This package is [ESM only](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c):
-Node 12+ is needed to use it and it must be `import`ed instead of `require`d.
-
-[npm][]:
+This package is [ESM only][esm].
+In Node.js (version 12.20+, 14.14+, 16.0+, or 18.0+), install with [npm][]:
 
 ```sh
 npm install xast-util-sitemap
 ```
 
-## Use
+In Deno with [`esm.sh`][esmsh]:
+
+```js
+import {sitemap} from 'https://esm.sh/xast-util-sitemap@1'
+```
+
+In browsers with [`esm.sh`][esmsh]:
 
-Say we have the following module, `example.js`
+```html
+<script type="module">
+  import {sitemap} from 'https://esm.sh/xast-util-sitemap@1?bundle'
+</script>
+```
+
+## Use
 
 ```js
 import {sitemap} from 'xast-util-sitemap'
@@ -66,7 +99,7 @@ const tree = sitemap([
 console.log(toXml(tree))
 ```
 
-Now, running `node example.js` yields (pretty printed):
+Yields (pretty printed):
 
 ```xml
 <?xml version="1.0" encoding="utf-8"?>
@@ -104,7 +137,7 @@ Now, running `node example.js` yields (pretty printed):
 
 ## API
 
-This package exports the following identifiers: `sitemap`.
+This package exports the identifier `sitemap`.
 There is no default export.
 
 ### `sitemap(data)`
@@ -114,12 +147,12 @@ Build a sitemap.
 ###### `data`
 
 URLs to build a sitemap for.
-`data` is an `Array.<url | Entry>`.
+`data` is an `Array<url | Entry>`.
 `url` is `string` and equivalent to an `{url: url}` entry.
 
 ###### Returns
 
-[`Root`][root] — [xast][] root.
+[xast][] root ([`Root`][root]).
 
 ### `Entry`
 
@@ -142,7 +175,7 @@ value for `new Date(x)`, optional).
 ###### `entry.alternate`
 
 Translations of the page, where each key is a [BCP 47][bcp47] tag and each value
-an entry (`Object<url | Entry>`, optional, example: `{nl:
+an entry (`Record<string, url | Entry>`, optional, example: `{nl:
 'https://example.nl/'}`).
 
 Alternate resources “inherit” fields (`modified`) from the entry they are
@@ -181,6 +214,18 @@ Or define them separately:
 ]
 ```
 
+## Types
+
+This package is fully typed with [TypeScript][].
+It exports the additional types `Alternate` and `Entry`.
+
+## Compatibility
+
+Projects maintained by the unified collective are compatible with all maintained
+versions of Node.js.
+As of now, that is Node.js 12.20+, 14.14+, 16.0+, and 18.0+.
+Our projects sometimes work with older versions, but this is not guaranteed.
+
 ## Security
 
 XML can be a dangerous language: don’t trust user-provided data.
@@ -198,8 +243,8 @@ of the `sitemap.xml` file is also an owner
 
 ## Contribute
 
-See [`contributing.md` in `syntax-tree/.github`][contributing] for ways to get
-started.
+See [`contributing.md`][contributing] in [`syntax-tree/.github`][health] for
+ways to get started.
 See [`support.md`][support] for ways to get help.
 
 This project has a [code of conduct][coc].
@@ -240,15 +285,23 @@ abide by its terms.
 
 [npm]: https://docs.npmjs.com/cli/install
 
+[esm]: https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c
+
+[esmsh]: https://esm.sh
+
+[typescript]: https://www.typescriptlang.org
+
 [license]: license
 
 [author]: https://wooorm.com
 
-[contributing]: https://github.com/syntax-tree/.github/blob/HEAD/contributing.md
+[health]: https://github.com/syntax-tree/.github
+
+[contributing]: https://github.com/syntax-tree/.github/blob/main/contributing.md
 
-[support]: https://github.com/syntax-tree/.github/blob/HEAD/support.md
+[support]: https://github.com/syntax-tree/.github/blob/main/support.md
 
-[coc]: https://github.com/syntax-tree/.github/blob/HEAD/code-of-conduct.md
+[coc]: https://github.com/syntax-tree/.github/blob/main/code-of-conduct.md
 
 [xast]: https://github.com/syntax-tree/xast