- Change SummaryState::add() -> SummaryState::update(), the
SummaryState::update() method is semantically aware of totals.
- Add an internal variable to the SummaryState class to keep track of the
elapsed simulation time.
This commit removes the restriction that cumulative totals are not
output in the case of creating OPM Extended Restart files. There
was a reason why we did not do this when the new restart facility
was introduced, but that reason no longer applies.
