Change setting in this VM when running.

        :param params: params to use with sub-command controlvm

        :returns: result of the command.

def _control_vm(self, params):
        """
        Change setting in this VM when running.

        :param params: params to use with sub-command controlvm

        :returns: result of the command.
        """

        args = shlex.split(params)
        result = yield from self.manager.execute("controlvm", [self._vmname] + args)
        return result