[nit] Add some usefule comment in CachedMessageStatus

src/network.rs

@@ -258,9 +258,9 @@ pub enum CachedMessageStatus {
     FaucetComplete,
     CipherWaitingTx,
     TxWaitingCipher,
-    SentWaitingConfirmation,
-    ReceivedMustConfirm,
-    MustSpendConfirmation,
+    SentWaitingConfirmation, // we're sender and wait for commited_in to be spent
+    ReceivedMustConfirm, // we're receiver and we spend commited_in to sender
+    MustSpendConfirmation, // we're sender and we must spend confirmed_by
     Complete,
 }