do not base64encode signatures in requests

plugins/trezor.py

@@ -2,7 +2,6 @@ from binascii import unhexlify
 from struct import pack
 from sys import stderr
 from time import sleep
-from base64 import b64encode, b64decode
 import unicodedata
 import threading
 import re
@@ -459,8 +458,7 @@ class TrezorWallet(BIP32_HD_Wallet):
             give_error(e)
         finally:
             self.plugin.handler.stop()
-        b64_msg_sig = b64encode(msg_sig.signature)
-        return str(b64_msg_sig)
+        return msg_sig.signature
 
     def sign_transaction(self, tx, password):
         if tx.is_complete():