Carbon helper function
carbon('2018-04-18') returns a carbon instance
- addWorkdays($count): self
- isHoliday()
- isWorkday()
italians holidays
- isLiberationDay()
- isRepublicDay()
- isImmaculateConceptionFeast()
- isAssumptionOfMaryFeast()
- isEpiphany()
- isDayBeforeChristmas()
- isChristmas()
- isSaintStephenDay()
- isSaintSylvesterDay()
- isWorkersDay()
