Bugfixing (#27)

* Enforce ordering on some metadata models
* Fix a 500 error while accessing flat pages
* Clean up HTML and fix cards (missing class)
* Make the "driver" app optional and disabled by default

ram/portal/templates/cards/consist.html

@@ -2,12 +2,10 @@
         <div class="card shadow-sm">
           <a href="{{ d.item.get_absolute_url }}">
           {% if d.item.image %}
-            <img src="{{ d.item.image.url }}" alt="Card image cap">
+            <img class="card-img-top" src="{{ d.item.image.url }}" alt="{{ d }}">
           {% else %}
             {% with d.item.consist_item.first.rolling_stock as r %}
-            {% for i in r.image.all %}
-              {% if forloop.first %}<img src="{{ i.image.url }}" alt="Card image cap">{% endif %}
-            {% endfor %}
+            <img class="card-img-top" src="{{ r.image.first.image.url }}" alt="{{ d }}"></a>
             {% endwith %}
           {% endif %}
           </a>