Log Message:
Update to 2019.9.26. From the changelog:

* Fix long blockquotes wrapping.
* Remove the trailing whitespaces that were added after wrapping list items \ 
& blockquotes.
* Fix memory leak when processing a document containing a ``<abbr>`` tag.
* Fix ``AttributeError`` when reading text from stdin.
* Fix ``UnicodeEncodeError`` when writing output to stdout.

Updating during the freeze for the bugfixes.