changed read_comic page width to auto to make better use of space.

margins were way too wide. and we could use that space on tablets.

comic/templates/comic/read_comic.html

@@ -10,6 +10,7 @@
     {% endfor %}
 {% endblock %}
 {% block content %}
+<div class="container comic_box">
 <center>
 <br/>
     {% if nav.q_next_to_directory %}
@@ -53,4 +54,5 @@
     {% endif %}
 </div>
 </center>
+</div>
 {% endblock %}