introduce new _ensure_correctly_typed method on fields, responsible
to ensure the value return by the widget is suitable for that kind
of field.
Also factorize date and time fields.
#! /bin/sh -ecase "$1" in remove) if [ -x "/etc/init.d/cubicweb-ctl" ]; then invoke-rc.d cubicweb-ctl stop || true fi ;;esac#DEBHELPER#exit 0