add motd api call

common/lib/verification_api.dart

@@ -85,6 +85,19 @@ class VerificationApi {
     _log.severe(response.body);
     return TicketResponse(null, error: VerificationErrorType.other);
   }
+
+  Future<String> getMotd() async {
+    final response = await _client.get(Uri.parse('$baseUrl/motd'));
+    _log.finer('getMotd received ${response.statusCode} status');
+
+    if (response.statusCode == 200) {
+      _log.finest(response.body);
+      return response.body;
+    } else {
+      _log.severe(response.body);
+      return '';
+    }
+  }
 }
 
 enum VerificationErrorType {