Unloads the plugin

        :raises: errors.PluginUninitError

def _unload(self, ):
        """Unloads the plugin

        :raises: errors.PluginUninitError
        """
        super(JB_MayaPlugin, self)._unload()
        try:
            if not jukeboxmaya.STANDALONE_INITIALIZED:
                self.uninit_ui()
        except Exception:
            log.exception("Unload Ui failed!")