Fix up topic filter to use new style

internewshid/hid/templates/hid/tabs/filters/category.html

 {% if category_options %}
 {% load i18n %}
-<div class="form-group table-button-group">
-<label class="col-sm-3 control-label" for="category-selector">{% trans "Topic" %}</label>
-<select id="category-selector" name="category" class="form-control">
+<div class="filter-topic form-group input-group">
+  <label class="col-sm-3 control-label" for="category-selector">{% trans "Topic" %}</label>
+  <div class="select-container">
+    <select id="category-selector" name="category" class="form-control">
         <option value=""{% if not request.GET.category %} selected="selected"{% endif %}>{% trans "All topics" %}</option>
         {% for cat in category_options %}
         <option value="{{ cat.0 }}"{% if cat.0 == request.GET.category %} selected="selected"{% endif %}>{{ cat.1 }}</option>
         {% endfor %}
-</select>
+    </select>
+  </div>
 </div>
 {% endif %}