Add Nemotron HF Support (continued from #31699)
Author: suhara
Pull request: yes

# What does this PR do?

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Add Nemotron HF support.

This PR is a continued PR from #31699, which was originally created by @suiyoubi. Later @gheinrich made changes based on the review comments by @ArthurZucker.

Let me create a new PR on behalf of @suiyoubi and @gheinrich due to their absence and high urgency of the PR.

Authors of the PR
- @suiyoubi
- @gheinrich

If the commits are squeezed and if possible, please set @suiyoubi as the author.


## Before submitting
- [ ] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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      Pull Request section?
- [ ] Was this discussed/approved via a Github issue or the [forum](https://discuss.huggingface.co/)? Please add a link
      to it if that's the case.
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      [here are tips on formatting docstrings](https://github.com/huggingface/transformers/tree/main/docs#writing-source-documentation).
- [ ] Did you write any new necessary tests?


## Who can review?

Anyone in the community is free to review the PR once the tests have passed. Feel free to tag
members/contributors who may be interested in your PR.

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Models:

- text models: @ArthurZucker
- 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
- ray/raytune: @richardliaw, @amogkam
- Big Model Inference: @SunMarc
- quantization (bitsandbytes, autogpt): @SunMarc

Documentation: @stevhliu

HF projects:

- accelerate: [different repo](https://github.com/huggingface/accelerate)
- datasets: [different repo](https://github.com/huggingface/datasets)
- diffusers: [different repo](https://github.com/huggingface/diffusers)
- rust tokenizers: [different repo](https://github.com/huggingface/tokenizers)

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Comments:
Hi @ArthurZucker,

Please review this new PR. Thank you!

@suiyoubi is back and he's made changes on the original PR. Let's continue using the original PR going forward. I'll close this PR. Sorry for confusion.