DRAFT: Add transformers backend support

[ArthurZucker]

Initial PR to add support for transformers as a backend! Following huggingface/transformers#35235, a bunch of models should already be supported, we are wramping up support for more models !!
Thanks @Isotr0py for the TP support!

Still have a few things to test / check

[github-actions]

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[ywang96]

Hello @ArthurZucker! This is very exciting!

I know this PR is still a draft, but could you provide some context on the scope of this effort? Is it to support any model on transformers?

[ArthurZucker]

Yep, overall this should support any model that is supported in transformers, were the cache is "simple" so for now, most of the decoder models and the encoder models for a single modularity!
For MultiModal models, we might need a little bit of extra work, but I thing LLAVA models should work out of the box!

We are refactor our models to make sure it's propagated to as many models as possible!

[ArthurZucker]

Might not have time to finish this week, will make it ready for next week 🎄
This should be minimal (no support fort Lora or at least I am not testing it ! This might. need to either call transformers's from pretrain, or replace modules similarly to TP)