Ciso8601

* Added Python 3.12 wheels

* Added Python 3.11 support
* Fix the build for PyPy2 ([116](https://github.com/closeio/ciso8601/pull/116))
* Added missing `fromutc` implementation for `FixedOffset` (113). Thanks davidkraljic
* Removed improper ability to call `FixedOffset`'s `dst`, `tzname` and `utcoffset` without arguments
* Fixed: `datetime.tzname` returns a `str` in Python 2.7, not a `unicode`
* Change `METH_VARARGS` to `METH_O`, enhancing performance. ([130](https://github.com/closeio/ciso8601/pull/130))
* Added support for ISO week dates, ([139](https://github.com/closeio/ciso8601/pull/139))
* Added support for ordinal dates, ([140](https://github.com/closeio/ciso8601/pull/140))

* Added Python 3.9 support
* Switched to using a C implementation of `timezone` objects.
* Much faster parse times for timestamps with timezone information
* ~2.5x faster on Python 2.7, ~10% faster on Python 3.9
* Thanks to [`pendulum`](https://github.com/sdispater/pendulum) and sdispater for the code.
* Python 2.7 users no longer need to install `pytz` dependency :smiley:
* Added caching of tzinfo objects
* Parsing is ~1.1x faster for subsequent timestamps that have the same time zone offset.
* Caching can be disabled at compile time by setting the `CISO8601_CACHING_ENABLED=0` environment variable
* Fixed a memory leak in the case where an invalid timestamp had a non-UTC timezone and extra characters

* Fixed a problem where non-ASCII characters would give bad error messages (84). Thanks olliemath.

* Fixed a problem where `ciso8601.__version__` was not working (80). Thanks ianhoffman.
* Added Python 3.8 support (83)
* Added benchmarking scripts (55)

* Fixed a problem where builds on Windows were not working (76). Thanks alexandrul and gillesdouaire, and sorry.