Fix path to posts

_includes/archive.html

@@ -5,7 +5,7 @@
   <h2>{{ yearMonth.name }}</h2>
   <ul>
     {% for post in yearMonth.items %}
-    <li><a href="{{ post.url }}">{{ post.title }}.</a> <span class="lead">{{ post.lead }}</span></li>
+    <li><a href="{{ post.url | remove_first: '/' }}">{{ post.title }}.</a> <span class="lead">{{ post.lead }}</span></li>
     {% endfor %}
   </ul>
   {% endfor %}