Put counts into the notification filters

We can filter notifications on the activity page by state.

This commit adds counts to those filters.

This is mainly so that we can consistently do the same thing on the job
page later on.

app/templates/components/pill.html

@@ -1,3 +1,5 @@
+{% from 'components/big-number.html' import big_number %}
+
 {% macro pill(
   title,
   items=[],
@@ -5,12 +7,19 @@
 ) %}
   <nav role='navigation' class='pill' aria-labelledby="pill_{{title}}">
     <h2 id="pill_{{title}}" class="visuallyhidden">{{title}}</h2>
-    {% for label, option, link in items %}
+    {% for label, option, link, count in items %}
       {% if current_value == option %}
-        <span aria-hidden="true">{{ label }}</span>
+        <span aria-hidden="true">
       {% else %}
-        <a href="{{ link }}">{{ label }}</a>
+        <a href="{{ link }}">
+      {% endif %}
+          {{ big_number(count, smaller=True) }}
+          <div class="pill-label">{{ label }}</div>
+      {% if current_value == option %}
+        </span>
+      {% else %}
+        </a>
       {% endif %}
     {% endfor %}
   </nav>
-{% endmacro %}
+{% endmacro %}