feat: support chameleon

[Gaiejj]

Description

Support SFT and DPO for the meta chameleon model.
Thanks to the contributions of transformer, we have achieved this integration with almost no effort.

If you need to use the chameleon model, please compile and install the latest version of transformers from the source code.

https://github.com/huggingface/transformers.git

Motivation and Context

For more details please refer to #18

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• Bug fix (non-breaking change which fixes an issue)
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Checklist

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• I have updated the documentation accordingly.

[htlou]

Fantastic Code! ❤️

[XuyaoWang]

LGTM.