db_bench does not output the "final" stats for a job

The "benchmark.sh" tool runs db_bench and looks for stats output like "Uptime", "Sum", and "L0" in the output. These statistics are printed periodically by the db_bench tool (based on a time interval). The stats do not appear to be printed when the job/thread is complete. This means a few things:
1 - If the job is too quick (does not run for stats interval time), no stats are printed
2 - The "final" stats are not printed, so the stats between the last interval and current are not available

When the job is complete, there should be a means of invoking "Stats::FinishedOps" that will cause any "unreported stats" to be dumped to the output file.