Use more sensible choice of period_range for `period_fast` feature
Use more sensible choice of period_range for `period_fast` feature

Periods searched should depend only on the range of times, rather than
the max time.

bnaul/mltsp,mltsp/mltsp,bnaul/mltsp,mltsp/mltsp,mltsp/mltsp,acrellin/mltsp,acrellin/mltsp,bnaul/mltsp,bnaul/mltsp,acrellin/mltsp,mltsp/mltsp,acrellin/mltsp,bnaul/mltsp,acrellin/mltsp,bnaul/mltsp,mltsp/mltsp,mltsp/mltsp,acrellin/mltsp