GitLab

* Model templates

* TensorFlow

* Remove pooler

* CI

* Tokenizer + Refactoring

* Encoder-Decoder

* Let's go testing

* Encoder-Decoder in TF

* Let's go testing in TF

* Documentation

* README

* Fixes

* Better names

* Style

* Update docs

* Choose to skip either TF or PT

* Code quality fixes

* Add to testing suite

* Update file path

* Cookiecutter path

* Update `transformers` path

* Handle rebasing

* Remove seq2seq from model templates

* Remove s2s config

* Apply Sylvain and Patrick comments

* Apply suggestions from code review
Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

* Last fixes from code review
Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>