Small suggestion about introduction

[EricGuo5513]

Hey, thanks for your amazing work for constructing this dataset. I encountered a small problem when I try to extract 3d joints from SMPL parameters. The scale doesn't seem right. It turns our we need to use "https://github.com/liruilong940607/smplx" instead of the original repo for "python setup.py install" after "pip install smplx". I feel it important to indicate that in the main introduction since it's a key step.

Just a minor suggestion. Hope you don't mind.