GitLab

* enable pxla training of stable diffusion 2.x models.

* run linter/style and run pipeline test for stable diffusion and fix issues.

* update xla libraries

* fix read me newline.

* move files to research folder.

* update per comments.

* rename readme.

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Co-authored-by: Juan Acevedo <jfacevedo@google.com>
Co-authored-by: Sayak Paul <spsayakpaul@gmail.com>