* Add Image2TextGenerationPipeline to supported pipelines
* Add Flax and Tensorflow support
* Add Flax and Tensorflow small tests
* Add default model for Tensorflow
* Add docstring
* Fix doc style
* Add tiny models for pytorch and flax
* Remove flax from pipeline.
Fix tests
* Use ydshieh/vit-gpt2-coco-en as a default for both PyTorch and Tensorflow
* Fix Tensorflow support
Co-authored-by: Olivier Dehaene <olivier@huggingface.co>