Unregister SDS from MDM/SIO Cluster
        :param sdsObj: ScaleIO SDS objecty
        :return: POST request response
        :rtype: Requests POST response object

def unregisterSds(self, sdsObj):
        """
        Unregister SDS from MDM/SIO Cluster
        :param sdsObj: ScaleIO SDS objecty
        :return: POST request response
        :rtype: Requests POST response object
        """
        self.conn.connection._check_login()
        response = self.conn.connection._do_post("{}/{}{}/{}".format(self.conn.connection._api_url, "instances/Sds::", sdsObj.id, 'action/removeSds'))    
        return response