SLA assessments should only be logged ONCE for the effecitve period, not each time the assessor happens to execute.
For example, if one sets a feed deadline of noon each day with 1 hour tolerance, we want to see a single assessment record logged if the deadline is met or determined to fail. I should see no other messages until the next day.
Added code to allow transactions to control when/if the metadata command is committed.
Updated the sla check logic to use the commit flag only if the sla assessment has changed