[Twisted-Python] towncrier releases 19.9.0 and 21.3.0rc1

[Kyle Altendorf]

Hi everyone,

I am announcing 2 twisted releases.

This is a bit more complicated than normal since 19.9.0rc1 was never 
followed by a non-RC release.

You can see a detailed checklist and discussion of this in #313 [0].

Relative to 19.9.0rc1, 19.9.0 contains a few readme fixes and the news 
fragments processed into the news file.

19.9.0 artifacts have been created [1] and 19.9.0 publishing is being 
held until after 21.3.0 to avoid a somewhat pointless intermediate step 
for developers that are using 'the latest non-pre release on PyPI' 
(presently 19.2.0).
  No real need for someone to get 19.9.0 now just to see 21.3.0 available 
next week.  The news for 21.3.0 is available for review [2].

21.3.0rc1 has been published and is open for a week for feedback before 
21.3.0 is planned to be released.

There are remaining bugs and important features.  But, it took long 
enough to get to this point that I consider it important to get 
something out.  Several people are waiting patiently [3].  As we find 
time to design and address the remaining issues, hopefully we can manage 
more frequent releases.

Please do let me know of any issues you find that are not already 
documented.  Or, if any of the documented ones should really be release 
blockers.  I sure hope we can get this out though.  :]

Cheers,
-kyle


[0]: https://github.com/twisted/towncrier/issues/313
[1]: 
https://github.com/twisted/towncrier/pull/331#issuecomment-803491163
[2]: https://github.com/twisted/towncrier/blob/21.3.0.rc1/NEWS.rst
[3]: https://github.com/twisted/towncrier/issues/269