Fix config deprecation (#3129)
* Better deprecation message
* Better deprecation message
* Better doc string
* Fixes
* fix more
* fix more
* Improve __getattr__
* correct more
* fix more
* fix
* Improve more
* more improvements
* fix more
* Apply suggestions from code review
Co-authored-by: Pedro Cuenca <pedro@huggingface.co>
* make style
* Fix all rest & add tests & remove old deprecation fns
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Co-authored-by: Pedro Cuenca <pedro@huggingface.co>
