Change simple_fciqmc to use accumulate \sum_j H_0j N_j and N_0 separately.
Change simple_fciqmc to use accumulate \sum_j H_0j N_j and N_0 separately.

hande-qmc/hande,hande-qmc/hande,hande-qmc/hande,ruthfranklin/hande,hande-qmc/hande,hande-qmc/hande