* add USE_I18N setting
* change setting name to ENABLE_TRANSLATION
* raise a warning in the UI when translation is disabled
* Misc cleanup
* Rename to TRANSLATION_ENABLED for consistency with other settings
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Co-authored-by: Anton Myasnikov <anton.myasnikov@nordigy.ru>
Co-authored-by: Jeremy Stretch <jstretch@netboxlabs.com>