Bugfixes and new feature

• v0.6, January 2023:
  • Internal improvements
• v0.5, December 2022:
  • Add new datetime_components() function.
  • Remove function create_iso8601_series() and add a hint on how to mimic
    the function using gretl commands.
  • Improve help text on how errors are handled for the iso8601_to_dates()
    function.
  • Both dates_to_iso8601() and date_to_iso8601() catch an eventual error
    and return zero in this error case.

Version 0.4

Add new iso8601_to_dates() function making it simple to cast a series in numeric ISO8601 format to a series of extended ISO8601 date string format.

Version 0.3

• Improved help text
• New gdate_to_iso8601() function

Version 0.2

Add new function numeric_to_extended_iso8601()

Initial version

v0.1

Update README.md