Adds and changes content

overrides/main.html

@@ -0,0 +1,8 @@
+{% extends "base.html" %}
+
+{% block header %}
+{{ super() }}
+<div style="color: white; text-align: center; padding: 10px; font-size: 20px;">
+    <strong>Announcement:</strong> This documentation is still in working progress.
+</div>
+{% endblock %}