Divide filters by headings and add clear button

aleksis/core/templates/core/group/list.html

@@ -14,11 +14,17 @@
     {% trans "Create group" %}
   </a>
 
+  <h5>{% trans "Filter groups" %}</h5>
   <form method="get">
     {% form form=groups_filter.form %}{% endform %}
     {% trans "Search" as caption %}
     {% include "core/partials/save_button.html" with caption=caption icon="search" %}
+    <button type="reset" class="btn red waves-effect waves-light">
+      <i class="material-icons left">clear</i>
+      {% trans "Clear" %}
+    </button>
   </form>
 
+  <h5>{% trans "Selected groups" %}</h5>
   {% render_table groups_table %}
 {% endblock %}

aleksis/core/templates/core/person/list.html

@@ -18,11 +18,17 @@
     </a>
   {% endif %}
 
+  <h5>{% trans "Filter persons" %}</h5>
   <form method="get">
     {% form form=persons_filter.form %}{% endform %}
     {% trans "Search" as caption %}
     {% include "core/partials/save_button.html" with caption=caption icon="search" %}
+    <button type="reset" class="btn red waves-effect waves-light">
+      <i class="material-icons left">clear</i>
+      {% trans "Clear" %}
+    </button>
   </form>
 
+  <h5>{% trans "Selected persons" %}</h5>
   {% render_table persons_table %}
 {% endblock %}