Add asynchronous call to database.

See file 'asynchronous.ts'.

backend/templates/message.html

@@ -1,7 +1,7 @@
-{% extends "base_with_list.html" %}
+{% extends "base_with_header.html" %}
 
-{% block content %}
+{% block main_container %}
 
-{{ message }}
+{{ message|markdown }}
 
 {% endblock %}