HPCC-9789 Add the option to add summary stats to the log file

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>
Merge pull request #4696 from ghalliday/issue9789

HPCC-9789 Add the option to add summary stats to the log file

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>