Fix references to `Transaction` after move

zebra-chain/src/lib.rs

@@ -5,5 +5,6 @@
 extern crate failure;
 
 pub mod block;
+pub mod serialization;
+pub mod transaction;
 pub mod types;
-pub mod serialization;

zebra-network/src/message.rs

@@ -9,7 +9,8 @@ use zebra_chain::{
     serialization::{
         ReadZcashExt, SerializationError, WriteZcashExt, ZcashDeserialize, ZcashSerialize,
     },
-    types::{BlockHeight, Sha256dChecksum, Transaction},
+    transaction::Transaction,
+    types::{BlockHeight, Sha256dChecksum},
 };
 
 use crate::meta_addr::MetaAddr;