Saves the name of the visible toolbars in the .ini file.

def save_visible_toolbars(self):
        """Saves the name of the visible toolbars in the .ini file."""
        toolbars = []
        for toolbar in self.visible_toolbars:
            toolbars.append(toolbar.objectName())
        CONF.set('main', 'last_visible_toolbars', toolbars)