Generates a base filename (without extension) for a calendar download, incorporating the year, date range, and/or location as available.
the year/date-range/location used to construct the filename; typically the same options passed to the calendar generator
a filename like hebcal_2020 or hebcal_1993_providence
hebcal_2020
hebcal_1993_providence
Generates a base filename (without extension) for a calendar download, incorporating the year, date range, and/or location as available.