def year(date)
      y = date.year.abs.to_s
      return [y, BCE_SUFFIX].join(' ') if (date.year <= -1)
      y
    end
def year(date)
      y = date.year.abs.to_s
      return [y, BCE_SUFFIX].join(' ') if (date.year <= -1)
      y
    end
Formats a CarbonDate::Date with year precision as a string
 Returns:
 A human-readable string representing the Date