Add a hidden book excerpt

Author: stojanovic

src/_layouts/post.html

@@ -23,6 +23,7 @@ <h1>{{ page.title }}</h1>
 
             {{ content }}
 
+            {% if page.show_related_posts == true %}
             <div class="related-posts">
                 <p>Read next:</p>
                 <ul>
@@ -34,6 +35,7 @@ <h1>{{ page.title }}</h1>
                     {% endif %}
                 </ul>
             </div>
+            {% endif %}
 
         </div><!-- main-content/col -->
     </div> <!--/row -->