GitLab

* Rework AutoFeatureExtractor.from_pretrained internal

* Custom feature extractor

* Add more tests

* Add support for custom feature extractor code

* Clean up

* Make sure custom configs work with Transformers

* Apply code review suggestions

* Allow dynamic modules to use relative imports

* Work for configs

* Fix last merge conflict

* Save code of registered custom objects

* Map strings to strings

* Fix test

* Add tokenizer

* Rework tests

* Tests

* Ignore fixtures py files for tests

* Tokenizer test + fix collection

* With full path

* Rework integration

* Fix typo

* Remove changes in conftest

* Test for tokenizers

* Add documentation

* Update docs/source/custom_models.mdx
Co-authored-by: Lysandre Debut <lysandre@huggingface.co>

* Add file structure and file content

* Add more doc

* Style

* Update docs/source/custom_models.mdx
Co-authored-by: Suraj Patil <surajp815@gmail.com>

* Address review comments
Co-authored-by: Lysandre Debut <lysandre@huggingface.co>
Co-authored-by: Suraj Patil <surajp815@gmail.com>