Prepare release 2.2.1

Prepare release 2.2

Prepare release 2.1

Prepare next iteration

2.0.5 (04-02-2019)

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 - Add mention of wagtail.contrib.settings in the documentation
 - Show languages in their local names.
 - Add W504 to flake8 ignore, it's changed in a newer version of flake8
 - Add env var WAGTAILTRANS_DISABLE_SIGNALS to disable many to many signal
 - Add a disable_for_loaddata decorator on signals
 - Add Simplified Chinese translation
 - Validate default_language to not exist in other_languages

Maintenance for Wagtail 2.3 (#139)

* Remove MSSQL testing

* Add Django 2.1 in the test range

* Tune Python versioning for Django 2.1

* Add newer Wagtail ranges 2.1, 2.2 and 2.3 stable

* Configure Python 3.7 for travis

* Use postgres v9.4 in the build

* Add Wagtail Python classifiers

* Bump sandbox versions

* Set to wagtail 2.3 rc1

* Update Postgres version to 9.6

Update changelog, bump version

Changelog and versiom bump

Bump version for 2.0.1

Prepare release for 2.0