added quit functionality to menubar in lite gui

lib/gui_lite.py

@@ -179,8 +179,8 @@ class MiniWindow(QDialog):
         electrum_menu.addSeparator()
         brain_seed = electrum_menu.addAction(_("&BrainWallet Info"))
         brain_seed.triggered.connect(self.actuator.show_seed_dialog)
-
-        electrum_menu.addAction(_("&Quit"))
+        quit_option = electrum_menu.addAction(_("&Quit"))
+        quit_option.triggered.connect(self.actuator.quit)
 
         view_menu = menubar.addMenu(_("&View"))
         expert_gui = view_menu.addAction(_("&Pro Mode"))
@@ -599,6 +599,9 @@ class MiniActuator:
     def show_seed_dialog(self):
         gui_qt.ElectrumWindow.show_seed_dialog(self.wallet)
 
+    def quit(self):
+        sys.exit(0)
+
 class MiniDriver(QObject):
 
     INITIALIZING = 0