add optional announcements to travelynx.conf

examples/travelynx.conf

@@ -5,6 +5,9 @@
 # 'localhost'. You can validate via 'perl -c travelynx.conf'.
 
 {
+	# Optional announcement, e.g. to indicate maintenance or backend issues.
+	#announcement => 'The IRIS backend is flaky. Real-time data may not be available.',
+
 	# Base URL of this travelynx installation, e.g. "https://travelynx.de" for
 	# travelynx.de. Used to identify this travelynx instance when performing API
 	# requests (so API providers know whom to contact case of issues) and for

templates/layouts/default.html.ep

@@ -117,6 +117,16 @@
 </div>
 % }
 
+% if (app->config->{announcement}) {
+<div class="container">
+	<div class="row">
+		<div class="col s12 caution-color white-text">
+			%= app->config->{announcement}
+		</div>
+	</div>
+</div>
+% }
+
 <div class="container">
 	% if (is_user_authenticated()) {
 		% my $acc = current_user();