Register QAction or QShortcut to Spyder main application,
        with shortcut (context, name, default)

def register_shortcut(self, qaction_or_qshortcut, context, name,
                          add_sc_to_tip=False):
        """
        Register QAction or QShortcut to Spyder main application,
        with shortcut (context, name, default)
        """
        self.shortcut_data.append( (qaction_or_qshortcut, context,
                                    name, add_sc_to_tip) )