Add link to Arch Linux RFC

Closes: #640

Author: jelly

templates/public/index.html

@@ -158,6 +158,8 @@ <h4>Development</h4>
             title="Official Arch projects (git)">Projects in Git</a></li>
         <li><a href="https://wiki.archlinux.org/title/DeveloperWiki"
             title="Developer Wiki articles">Developer Wiki</a></li>
+        <li><a href="https://rfc.archlinux.page"
+            title="Arch Request for Comments">Request for Comments</a></li>
         <li><a href="/groups/"
             title="View the available package groups">Package Groups</a></li>
         <li><a href="/todo/"