prepare for separation of ecc module:

- move encrypt/sign functions elsewhere
- remove local dependencies in ecc.py, ecc_fast.py (except logging)

electrum/commands.py

@@ -716,7 +716,7 @@ class Commands:
         """Verify a signature."""
         sig = base64.b64decode(signature)
         message = util.to_bytes(message)
-        return ecc.verify_usermessage_with_address(address, sig, message)
+        return bitcoin.verify_usermessage_with_address(address, sig, message)
 
     @command('wp')
     async def payto(self, destination, amount, fee=None, feerate=None, from_addr=None, from_coins=None, change_addr=None,
@@ -910,7 +910,7 @@ class Commands:
         except TypeError:
             raise UserFacingException(f"message must be a string-like object instead of {repr(message)}")
         public_key = ecc.ECPubkey(bfh(pubkey))
-        encrypted = public_key.encrypt_message(message)
+        encrypted = crypto.ecies_encrypt_message(public_key, message)
         return encrypted.decode('utf-8')
 
     @command('wp')