GitLab

* add tokenizer_summary to es/_toctree.yml

* add tokenizer_summary to es/

* fix link to Transformes XL in en/

* translate until Subword tokenization section

* fix GPT link in en/

* fix other GPT link in en/

* fix typo in en/

* translate the doc

* run make fixup

* Remove .md in Transformer XL link

* fix some link issues in es/

* fix typo