Updated openstack/openstack
Project: openstack/nova  f97adcbb1407befe2a9fda08e9e25a812cd8cc5f
null
Abstract add_timestamp out of ComputeDriverCPUMonitor class

Move add_timestamp decorator into ResourceMonitorBase class,
then other monitor metrics can reuse it.

Change-Id: I060353b9e194b1882549fec07fc2a486aeb1fce0