Added settings to control custom fiscal periods

New settings:
- UseCustomFiscalPeriods 
-- Use CustomFiscalPeriods in case you need arbitrary definition of weekly fiscal years 
-- Set "UseCustomFiscalPeriods" to TRUE in order to use CustomFiscalPeriods 

- IgnoreWeeklyFiscalPeriods
-- Set "IgnoreWeeklyFiscalPeriods" to TRUE in order to ignore the WeeklyFiscalPeriods
-- You should set IgnoreWeeklyFiscalPeriods to TRUE only when UseCustomFiscalPeriods is TRUE, too

Author: marcosqlbi