Add NaViT

[awsaf49]

I think it would be nice to have NaViT model as it specifically addresses, "resizing images to a fixed resolution before
processing them with the model" aka "inputs of arbitrary resolutions and aspect ratios".

Paper: https://arxiv.org/pdf/2307.06304.pdf
Code: Hasn't been released yet :(

[leondgarse]

Just added in TODO list, maybe have to wait till they release it.