add a tagging system to the website

template/components/_doc.hbs

@@ -4,6 +4,14 @@
             {{#if (ne page.tree_path 'index')}}
             <header>
                 <h1 class="page-title"><a href="{{ config.site }}/{{ page.tree_path }}">{{ page.title }}</a></h1>
+                <ul class="feeds">
+                    {{#each page.feeds as |feed|}}
+                    <li>
+                        <time datetime="{{ feed.updated }}">{{ iso_date feed.updated }}</time>
+                        {{#if (gt (len page.feeds) 0)}}<span class="source-feed">[<a href="{{ feed.url }}">{{ feed.name }}</a>]</span>{{/if}}
+                    </li>
+                    {{/each}}
+                </ul>
             </header>
             {{/if}}