Support parsing dates given in alternate calendars

[thatbudakguy]

Dates using alternative calendars in Cocina use the form:

{
  value: '1544-02-02',
  type: 'creation',
  note: [{
    value: 'Julian',
    type: 'calendar'
  }]
}

The cocina-models docs suggest the calendar note type can have values "Gregorian", "Julian", "Hijri calendar", "Islamic", and "Hebrew".

[thatbudakguy]

So far it's been really hard to find instances of this "in the wild".

cs483wz9097 has:

{ "value": "L'an 5", "type": "Revolutionary calendar" }

bb347yt6278 has:

{ "value": "1309", "type": "Hijri calendar" }

...but these don't match the current cocina-models spec.

Additionally, both these records have parallel event dates that seem to describe the same event and are not using the alternative calendar, making the non-gregorian ones not strictly needed or useful for parsing.