If assign_try fails to assign all the moves, we check if all the moves of each
shipment and production are assigned and then assign them.
Also we remove the boolean return which makes no more sense.
Closes#7006
The fiscal years are created centered on the passed date such that if the
current day change during the execution, the fiscal year is still usable.
Also fiscal year can be created for a range of dates such that it is guarantee
that the dates are in the fiscal year.
And finally remove datetime and dateutil import when they are not used.
Closes#9977
Cédric Krier