Better support of date and period on move

The validity of the date and period is done with a validation but it could be done by a domain such that searching a period will be filtered.
For now it is period centric as the date is compute from it but indeed it will be more flexible that depending on which field is changed we deduce the other one.
Also by default when we need to set the date from the period we always use the start date but I think it will be smarter to use the start date if it is a future period and the end date if it is a period in the past.