* Add proper namespace scoping to a 'SumStats::process_epoch_result'
scheduled event.
* Fix iterator invalidation within 'SumStats::process_epoch_result'
* Give 'SumStats::process_epoch_result' a copy of the result table so
that the SumStats framework can clear the original and move on to the
next epoch immediately.
* The previous baseline of the basic sumstats unit test did look wrong
to me and probably was actually indicative of the iterator invalidation
problem.
Thanks to Jim Mellander for reporting the issues.