Show holidays in visited countries on trip page

Closes: #112

templates/trip_page.html

@@ -72,6 +72,25 @@
     {% for item in trip.travel %} {{ row[item.type](item) }} {% endfor %}
   </div>
 
+  <div class="mt-3">
+  <h4>Holidays</h4>
+
+  <table class="table table-hover w-auto">
+  {% for item in holidays %}
+    {% set country = get_country(item.country) %}
+    <tr>
+      {% if loop.first or item.date != loop.previtem.date %}
+        <td class="text-end">{{ display_date(item.date) }}</td>
+      {% else %}
+        <td></td>
+      {% endif %}
+      <td>{{ country.flag }} {{ country.name }}</td>
+      <td>{{ item.display_name }}</td>
+    </tr>
+  {% endfor %}
+  </table>
+  </div>
+
   <p>
     {% if prev_trip %}
       previous: {{ trip_link(prev_trip) }} ({{ (trip.start - prev_trip.end).days }} days)