Make errors more readable in template

Instead of printing the `repr()` of the row, leading to `OrderedDict([(u'col1', u'val1'), (u'col2', u'val2'), …])`, just print `val1, val2, …`.

import_export/templates/admin/import_export/import.html

@@ -28,12 +28,7 @@ <h1>{% trans "Import" %}</h1>
 
     <p>
       {% trans "This importer will import the following fields: " %}
-      {% for f in fields  %}
-        {% if forloop.counter0 %}
-        ,
-        {% endif %}
-        <code>{{ f }}</code>
-      {% endfor %}
+      <code>{{ fields|join:", " }}</code>
     </p>
 
     <fieldset class="module aligned">
@@ -73,7 +68,7 @@ <h2>{% trans "Errors" %}</h2>
         {% for error in errors %}
           <li>
             {% trans "Line number" %}: {{ line }} - {{ error.error }}
-            <div>{{ error.row }}</div>
+            <div><code>{{ error.row.values|join:", " }}</code></div>
             <div class="traceback">{{ error.traceback|linebreaks }}</div>
           </li>
         {% endfor %}