misc python3 updates:

- use jsonrpclib-pelix
 - update the kivy gui
 - update plugins

gui/qt/transaction_dialog.py

@@ -42,7 +42,7 @@ from electrum.bitcoin import base_encode
 from electrum.i18n import _
 from electrum.plugins import run_hook
 
-from lib.util import bfh
+from electrum.util import bfh
 from .util import *
 
 dialogs = []  # Otherwise python randomly garbage collects the dialogs...