lightning: add missing import, set console to none initially

gui/kivy/uix/dialogs/lightning_payer.py

@@ -1,6 +1,7 @@
 from kivy.lang import Builder
 from kivy.factory import Factory
 from electrum_gui.kivy.i18n import _
+import electrum.lightning as lightning
 
 Builder.load_string('''
 <LightningPayerDialog@Popup>

lib/lightning.py

@@ -601,6 +601,7 @@ class LightningRPC:
         super(LightningRPC, self).__init__()
         self.queue = queue.Queue()
         self.subscribers = []
+        self.console = None
     # overridden
     async def run(self, netAndWalLock):
       while asyncio.get_event_loop().is_running():