Add rehype-scroll-to-top, rehype-smenatic-images to list of plugins

Closes GH-163.

Reviewed-by: Christian Murphy <[email protected]>
Reviewed-by: Remco Haszing <[email protected]>
Reviewed-by: Titus Wormer <[email protected]>

Author: benjamincharity

doc/plugins.md

@@ -169,11 +169,15 @@ The list of plugins:
     — rewrite element with rehype
 *   [`rehype-sanitize`](https://github.com/rehypejs/rehype-sanitize)
     — sanitize HTML
+*   [`rehype-scroll-to-top`](https://github.com/benjamincharity/rehype-scroll-to-top)
+    — customizable “Scroll to Top” and “Scroll to Bottom” links
 *   [`rehype-section`](https://github.com/agentofuser/rehype-section)
     — wrap headings and their contents into nested `<section>` elements
 *   [`rehype-sectionize`](https://github.com/hbsnow/rehype-sectionize)
     — wrap headings and their contents into nested `<section>` elements,
     with attributes
+*   [`rehype-semantic-images`](https://github.com/benjamincharity/rehype-semantic-images)
+    — enrich HTML images with semantic elements and customizable features
 *   [`rehype-shift-heading`](https://github.com/rehypejs/rehype-shift-heading)
     — change the rank of headings
 *   [`rehype-shiki`](https://github.com/rsclarke/rehype-shiki)