py-cftime: updated to 1.4.1

version 1.4.1 (release tag v1.4.1.rel)
======================================
 * Restore use of calendar-specific sub-classes in `cftime.num2date`,
   `cftime.datetime.__add__`, and `cftime.datetime.__sub__`.  The use of them
   will be removed in a later release.
 * add 'fromordinal' static method to create a cftime.datetime instance
   from a julian day ordinal and calendar (inverse of 'toordinal').

version 1.4.0 (release tag v1.4.0.rel)
======================================
 * `cftime.date2num` will now always return an array of integers, if the units
   and times allow.  Previously this would only be true if the units were
   'microseconds'.  In other circumstances, as before, `cftime.date2num`
   will return an array of floats.
 * Rewrite of julian day/calendar functions (_IntJulianDayToCalendar and
   _IntJulianDayFromCalendar) to remove GPL'ed code.  cftime license
   changed to MIT (to be consistent with netcdf4-python).
 * Added datetime.toordinal() (returns julian day, kwarg 'fractional'
   can be used to include fractional day).
 * cftime.datetime no longer uses calendar-specific sub-classes.

version 1.3.1 (release tag v1.3.1rel)
=====================================
 * fix for issue 211 bug in masked array handling in date2num)
 * switch from travis/appveyor to github actions for CI/CD.
 * switch to cython language_level=3 (no more support for python 2).
 * add __init__.py to test dir so pytest coverage works again. Add Coveralls
   step to github actions workflow to upload coverage data to coveralls.io
 * move package under 'src' directory so cftime can be imported
   from install dir

version 1.3.0 (release tag v1.3.0rel)
=====================================
 * zero pad years in strtime
 * have cftime.datetime constuctor create 'calendar-aware' instances (default is
   'standard' calendar, if calendar='' or None the instance is not calendar aware and some
   methods, like dayofwk, dayofyr, __add__ and __sub__, will not work).
   The calendar specific sub-classes are now deprecated, but remain for now
   as stubs that just instantiate the base class and override __repr__.
 * update regex in _cpdef _parse_date so reference years with more than four
   digits can be handled.
 * Change default calendar in cftime.date2num from 'standard' to None
   (calendar associated with first input datetime object is used).
 * add `cftime.datetime.tzinfo=None` for compatibility with python datetime
  .

version 1.2.1 (release tag v1.2.1rel)
=====================================
 * num2date uses 'proleptic_gregorian' scheme when basedate is post-Gregorian but date is pre-Gregorian
  .
 * fix 1.2.0 regression (date2num no longer works with numpy scalar array inputs).
 * Fix for issue 187 (have date2num round to the nearest second when within 1
   microsecond).
 * Fix for issue 189 (leap years calculated incorrectly for negative years in
   proleptic_gregorian calendar).

version 1.2.0 (release tag v1.2.0rel)
=====================================
 * Return the default values of dayofwk and dayofyr when calendar
   is ''.
 * fix treatment of masked arrays in num2date and date2num.
   Also make sure masked arrays are output from num2date/date2num if
   masked arrays are input.
 * Where possible, use timedelta arithmetic to decode times exactly within
   num2date.
 * Make taking the difference between two cftime datetimes to produce a
   timedelta exact to the microsecond; depending on the units encoding,
   this enables date2num to be exact as well.
 * utime.date2num/utime.num2date now just call module level functions.
   JulianDayFromDate/DateFromJulianDay no longer used internally.


(adam)