Repo is too big

This repo has a super long checkout time since it has a ton of history. A regular checkout git clone https://github.com/pytorch/pytorch.github.io.git takes 15 minutes on a devbig. A shallow checkout with --depth=1 takes only 1 minute

We have some options for fixing:

1. Delete the history. I don't use this repo that often so I'm not sure how useful it is. We can also delete it in a smarter way, such as only deleting history from commits 100-N, but keep commits 1-100, or keep every 10th commit or something. Deleting everything (rm -rf .git; git init; git add .; git c -m"test") shrinks the .git folder from 4 GB to 300 MB on my machine, so this is a viable fix if we don't care about the history at all. We could also move the history to a non-default branch (site-old or something) and start fresh. We'd have to do this regularly though since we're not actually fixing the root cause.
2. Split out the big parts: the entire docs/ folder lives in pytorch/pytorch. We could move that to its own repo (and maybe its own subdomain, with pytorch.org/docs redirecting there). This would keep the fast moving auto generated parts away from the main repo and enable faster development on blog posts/etc since they don't have to deal with the docs folder.

Start by comparing the repository's regular clone with the reported --depth=1 checkout and inspect the size of .git. Review the two proposed approaches: rewriting or relocating history, and splitting the docs/ folder from pytorch/pytorch. The issue does not select an approach, so done is not defined until the desired repository structure and history policy are decided.