Uninstall and delete NApps.

        For local installations, do not delete code outside install_path and
        enabled_path.

def uninstall(cls, args):
        """Uninstall and delete NApps.

        For local installations, do not delete code outside install_path and
        enabled_path.
        """
        mgr = NAppsManager()
        for napp in args['<napp>']:
            mgr.set_napp(*napp)
            LOG.info('NApp %s:', mgr.napp_id)
            if mgr.is_installed():
                if mgr.is_enabled():
                    cls.disable_napp(mgr)
                LOG.info('  Uninstalling...')
                mgr.uninstall()
                LOG.info('  Uninstalled.')
            else:
                LOG.error("  NApp isn't installed.")