'Updates a logical router.
For a full list of available parameters, please refer to the official
API reference:
http://developer.openstack.org/api-ref/networking/v2/index.html#update-router'

def update_router(self, router_id, **kwargs):

    uri = ('/routers/%s' % router_id)
    update_body = {'router': kwargs}
    return self.update_resource(uri, update_body)
