Option to have a message on the ban page

Conflicts:
	inc/config.php

templates/banned.html

@@ -76,6 +76,8 @@
 		</span>
 	</p>
 	<p>{% trans %}Your IP address is{% endtrans %} <strong>{{ ban.ip }}</strong>.</p>
+
+	<p>{{ config.ban_page_message }}</p>
 </div>
 {% endfilter %}