Synchronization should check dateSysMetaModified when adding tasks to processing queue
When retrieving PIDs to synchronize using listObjects against a Member Node, the dateSysMetaModified should be checked to be sure that the entry is newer than the earliest time requested in the listObjects call.
This is a protective measure to ensure that the CN does not continually try and synchronize old content for a MN that is misbehaving and not responding correctly to a timeslice request on listObjects.
fixes #7955. Added check that the modification date of the objectInfo is within the harvest window.