[imp] Semantic structure improvements

lib/site_template/_layouts/page.html

@@ -1,14 +1,14 @@
 ---
 layout: default
 ---
-<div class="post">
+<article class="post">
 
   <header class="post-header">
     <h1 class="post-title">{{ page.title }}</h1>
   </header>
 
-  <article class="post-content">
+  <div class="post-content">
     {{ content }}
-  </article>
+  </div>
 
-</div>
+</article>

lib/site_template/_layouts/post.html

@@ -1,15 +1,15 @@
 ---
 layout: default
 ---
-<div class="post"  itemscope itemtype="http://schema.org/BlogPosting">
+<article class="post"  itemscope itemtype="http://schema.org/BlogPosting">
 
   <header class="post-header">
     <h1 class="post-title" itemprop="name headline">{{ page.title }}</h1>
     <p class="post-meta"><time datetime="{{ page.date | date_to_xmlschema }}" itemprop="datePublished">{{ page.date | date: "%b %-d, %Y" }}</time>{% if page.author %} • <span itemprop="author" itemscope itemtype="http://schema.org/Person"><span itemprop="name">{{ page.author }}</span></span>{% endif %}{% if page.meta %} • {{ page.meta }}{% endif %}</p>
   </header>
 
-  <article class="post-content" itemprop="articleBody">
+  <div class="post-content" itemprop="articleBody">
     {{ content }}
-  </article>
+  </div>
 
-</div>
+</article>