fix offline signing: redeemPubkey was missing

lib/transaction.py

@@ -722,4 +722,5 @@ class Transaction:
             txin['address'] = item['address']
             txin['scriptPubKey'] = item['scriptPubKey']
             txin['redeemScript'] = item.get('redeemScript')
+            txin['redeemPubkey'] = item.get('redeemPubkey')
             txin['KeyID'] = item.get('KeyID')

lib/wallet.py

@@ -1207,7 +1207,8 @@ class Wallet:
         tx = self.make_unsigned_transaction(outputs, fee, change_addr, domain)
         keypairs = {}
         self.add_keypairs_from_wallet(tx, keypairs, password)
-        self.sign_transaction(tx, keypairs)
+        if keypairs:
+            self.sign_transaction(tx, keypairs)
         return tx