GitLab

* Add epsilon- and eta-sampling.

Add epsilon- and eta-sampling, following the official code from https://github.com/john-hewitt/truncation-sampling and adapting to be more configurable, as required by Huggingface transformers.

* Add unit tests for epsilon- and eta-sampling.

* Black: fix code formatting.

* Fix docstring spacing.

* Clean up newlines.

* Fix implementation bugs and their associated tests.

* Remove epsilon- and eta-sampling parameters from PretrainedConfig.

* Clarify and clean up the documentation.

* Remove parameters for PretrainedConfig test.