Default to Julian calendar for dates before 5 October 1582

[Thunderforge]

When the Gregorian calendar was first introduced to replace the Julian calendar, Thursday 4 October 1582 was followed by Friday 15 October 1582. Therefore, we can safely assume that any date in this format before 5 October 1582 is in the Julian calendar and not the Gregorian calendar.

(Note that the final country to transition from the Julian calendar to the Gregorian calendar was Greece, with 15 Feb 1923 followed by 1 Mar 1923. Thus we can safely assume that any date 16 February 1923 or later is a Gregorian date. Any date in between could potentially be either calendar, depending on the country).

I would like to see QuickStatements default to the Julian calendar for all dates before 5 October 1582. A configuration option to specify a calendar type would be even better, but is not strictly necessary for this issue.