Cleanup

Move state machine executors into seperate files

Remove check for ack message from Alice. Seems like a bad idea to
rely on an acknowledgement message instead of looking at the
blockchain.

Fix warnings

swap/src/lib.rs

@@ -6,6 +6,7 @@ pub mod bitcoin;
 pub mod bob;
 pub mod bob_simple;
 pub mod cli;
+pub mod io;
 pub mod monero;
 pub mod network;
 pub mod recover;