fix article list links

_includes/article_list.html

@@ -1,4 +1,4 @@
 <article class="list">
   <time datetime="{{ post.date | datetime | date_to_xmlschema }}" pubdate>{{ post.date | date: "%B %d" }}</time>
-  <a href="/{{ post.url }}">{{post.title}}</a>
+  <a href="{{ post.url }}">{{post.title}}</a>
 </article>