Update babel to 2.9.1

[pyup-bot]

This PR updates babel from 2.8.0 to 2.9.1.

Changelog

2.9.1

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Bugfixes
~~~~~~~~

* The internal locale-data loading functions now validate the name of the locale file to be loaded and only
allow files within Babel's data directory.  Thank you to Chris Lyne of Tenable, Inc. for discovering the issue!

2.9.0

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Upcoming version support changes
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

* This version, Babel 2.9, is the last version of Babel to support Python 2.7, Python 3.4, and Python 3.5.

Improvements
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* CLDR: Use CLDR 37 – Aarni Koskela (734)
* Dates: Handle ZoneInfo objects in get_timezone_location, get_timezone_name - Alessio Bogon (741)
* Numbers: Add group_separator feature in number formatting - Abdullah Javed Nesar (726)

Bugfixes
~~~~~~~~

* Dates: Correct default Format().timedelta format to 'long' to mute deprecation warnings – Aarni Koskela
* Import: Simplify iteration code in "import_cldr.py" – Felix Schwarz
* Import: Stop using deprecated ElementTree methods "getchildren()" and "getiterator()" – Felix Schwarz
* Messages: Fix unicode printing error on Python 2 without TTY. – Niklas Hambüchen
* Messages: Introduce invariant that _invalid_pofile() takes unicode line. – Niklas Hambüchen
* Tests: fix tests when using Python 3.9 – Felix Schwarz
* Tests: Remove deprecated 'sudo: false' from Travis configuration – Jon Dufresne
* Tests: Support Py.test 6.x – Aarni Koskela
* Utilities: LazyProxy: Handle AttributeError in specified func – Nikiforov Konstantin (724)
* Utilities: Replace usage of parser.suite with ast.parse – Miro Hrončok

Documentation
~~~~~~~~~~~~~

* Update parse_number comments – Brad Martin (708)
* Add __iter__ to Catalog documentation – CyanNani123

2.8.1

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This is solely a patch release to make running tests on Py.test 6+ possible.

Bugfixes
~~~~~~~~

* Support Py.test 6 - Aarni Koskela (747, 750, 752)

Links

• PyPI: https://pypi.org/project/babel
• Changelog: https://pyup.io/changelogs/babel/
• Homepage: http://babel.pocoo.org/
• Docs: https://pythonhosted.org/Babel/

[pyup-bot]

Closing this in favor of #52