Correct shift sanity check when analysing multiple files.
Correct shift sanity check when analysing multiple files.

Sometimes it is useful to analyse multiple output files in a combined
fashion (e.g. after restarting a calculation).  The shift sanity check
(that data was analysed from only after the shift turned on) did not
previously handle this case.

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