Update datastream versionable setting.

        :param pid: object pid
        :param dsID: datastream id
        :param versionable: boolean
        :returns: boolean success

def setDatastreamVersionable(self, pid, dsID, versionable):
        '''Update datastream versionable setting.

        :param pid: object pid
        :param dsID: datastream id
        :param versionable: boolean
        :returns: boolean success
        '''
        # /objects/{pid}/datastreams/{dsID} ? [versionable]
        http_args = {'versionable': versionable}
        url = 'objects/%(pid)s/datastreams/%(dsid)s' % {'pid': pid, 'dsid': dsID}
        response = self.put(url, params=http_args)
        # returns response code 200 on success
        return response.status_code == requests.codes.ok