Make the author name a h1 (instead of h2) for SEO

_includes/author.html

@@ -4,6 +4,6 @@
     src="{{ site.author.avatar }}"
     alt="{{ site.author.username }}"
   />
-  <h2 class="author-name">{{ site.author.name }}</h2>
+  <h1 class="author-name">{{ site.author.name }}</h1>
   <p class="author-bio">{{ site.author.bio }}</p>
 </div>