Add onion_messages module

Git makes it difficult to add parts of a new file unless the file is already tracked.
This was the quickest workaround to split up adding onion_message.rs in parts

Author: valentinewallace

lightning/src/ln/mod.rs

@@ -28,6 +28,7 @@ pub mod functional_test_utils;
 pub mod channelmanager;
 pub mod inbound_payment;
 pub mod msgs;
+pub mod onion_message;
 pub mod peer_handler;
 pub mod chan_utils;
 pub mod features;

lightning/src/ln/onion_message.rs

@@ -0,0 +1,10 @@
+// This file is Copyright its original authors, visible in version control
+// history.
+//
+// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
+// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
+// You may not use this file except in accordance with one or both of these
+// licenses.
+
+//! Onion Messages: sending, receiving, forwarding, and ancillary utilities live here