print trezor error message

plugins/trezor.py

@@ -101,11 +101,12 @@ class Plugin(BasePlugin):
                 d = HidTransport.enumerate()[0]
                 self.transport = HidTransport(d)
             except:
+                import traceback
+                traceback.print_exc(file=sys.stdout)
                 give_error('Could not connect to your Trezor. Please verify the cable is connected and that no other app is using it.')
             self.client = QtGuiTrezorClient(self.transport)
             self.client.handler = self.handler
             self.client.set_tx_api(self)
-            #self.client.clear_session()# TODO Doesn't work with firmware 1.1, returns proto.Failure
             self.client.bad = False
             if not self.atleast_version(1, 2, 1):
                 give_error('Outdated Trezor firmware. Please update the firmware from https://www.mytrezor.com')