Add Florence2 support
Author: D4ve-R
Pull request: yes

# What does this PR do?

Add support for microsoft/Florence2

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## Who can review?

Anyone in the community is free to review the PR once the tests have passed. Feel free to tag
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Models:

- text models: @ArthurZucker and @younesbelkada
- vision models: @amyeroberts
- speech models: @sanchit-gandhi
- graph models: @clefourrier

Library:

- flax: @sanchit-gandhi
- generate: @zucchini-nlp (visual-language models) or @gante (all others)
- pipelines: @Narsil
- tensorflow: @gante and @Rocketknight1
- tokenizers: @ArthurZucker
- trainer: @muellerzr and @SunMarc

Integrations:

- deepspeed: HF Trainer/Accelerate: @muellerzr
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- quantization (bitsandbytes, autogpt): @SunMarc and @younesbelkada

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- rust tokenizers: [different repo](https://github.com/huggingface/tokenizers)

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Comments:
Command to check diff from [original impl](https://huggingface.co/microsoft/Florence-2-large/tree/main)

```sh
FILE=configuration_florence2.py
git diff --no-index <(curl -s https://huggingface.co/microsoft/Florence-2-large/raw/main/$FILE) src/transformers/models/florence/$FILE
```

@D4ve-R Let us know when it's ready for review! 

@D4ve-R I share some script that finetuning florence-2. This might not be include in this PR since this is unofficial but share for your intereset.
Dataset : https://huggingface.co/datasets/danelcsb/cavity
Model : https://huggingface.co/danelcsb/Florence-2-FT-cavity/tree/main
Demo : https://9d0f63918f67be84d1.gradio.live/ (Can be down without notification)
Finetuning code : https://github.com/SangbumChoi/florence2-finetuning/blob/main/train_object_detection.py
Reference
[https://colab.research.google.com/github/roboflow-ai/notebooks/blob/main/notebooks/how-to[…]rence-2-on-detection-dataset.ipynb?ref=blog.roboflow.com](https://colab.research.google.com/github/roboflow-ai/notebooks/blob/main/notebooks/how-to-finetune-florence-2-on-detection-dataset.ipynb?ref=blog.roboflow.com)
https://colab.research.google.com/drive/1Y8GVjwzBIgfmfD3ZypDX5H1JA_VG0YDL?usp=sharing#scrollTo=OQzv9cEVOwbV
https://colab.research.google.com/drive/1hKDrJ5AH_o7I95PtZ9__VlCTNAo1Gjpf?usp=sharing#scrollTo=zqDWEWDcaSxN

@D4ve-R Thanks for all your work on this so far! 

I think we can close this PR. The Florence 2 model is available directly on the hub to be used within transformers e.g.: https://huggingface.co/microsoft/Florence-2-large

Apologies for not noticing this sooner 

@amyeroberts no worries! It was really fun and a great experience to learn something.

@D4ve-R Hi, even though the PR might be closed, I would recommend you to keep this branch alive in your repo. I think this might be valuable when we also consider finetuning florence2 model! Nice work :)