add event_place to fetmeeting admin and template

fet2020/templates/posts/show.html

@@ -122,6 +122,10 @@
                 Ende: {{ post.event_end|date:"d. F Y" }} {{ post.event_end|time:"H:i" }}<br>
             {% endif %}
 
+            {% if post.event_place %}
+                Ort: {{ post.event_place }}
+            {% endif %}
+
             {% if post.event_start %}
                 {% include 'posts/partials/_date_box.html' %}
             {% endif %}