Request to add new paper

[cyhzz1]

Hi,

Thanks for hard working to maintaining the repository. I'd like to request the addition of the Panoptic Narrative Grounding to the repository. Although the authors call it "Grounding", the task itself looks like Segmentation, which is suitable for this repository.

Paper: https://arxiv.org/abs/2109.04988
Project: https://bcv-uniandes.github.io/panoptic-narrative-grounding/

Thanks.