[Feature Request] Implementing YOLO v4 / v5 / .. ?

[innat]

Hello, @zzh8829 great repo.

I was wondering if you've planned to add other improved versions of YoLo. I think it would be great to have all of them in one place. What do you think? Any plan on that? Also, Is PR welcomed? Thanks.

FYI, I've encountered another great repo, which contains YoLo version v2, v3, v4, v5. But I found that it didn't follow the TF 2.x best practice.