Avoid duplication on README <-> website

[NoraLoose]

Closes #50

Since the README is at the same time used as the website landing page (after copying it to website/), I had to use html links (rather than relative paths within the github repo). Not optimal but maybe the best option we have available?

I also included the evaluation notebooks on the website.

It might be easier to see what this PR does after merging it and the website actually builds.

[NoraLoose]

I noticed that we may need a project structure as suggested in #23 after all. It will be a bit awkward on the website landing page, but maybe ok. I will leave it for a future PR.

[cisaacstern]

I noticed that we may need a project structure as suggested in #23 after all. It will be a bit awkward on the website landing page, but maybe ok. I will leave it for a future PR.

@NoraLoose how about #23 goes into an ARCHITECTURE.md file in the repo root (blog post on this here: https://matklad.github.io/2021/02/06/ARCHITECTURE.md.html) and then is linked from the README?

[NoraLoose]

Since the README is at the same time used as the website landing page (after copying it to website/), I had to use html links (rather than relative paths within the github repo). Not optimal but maybe the best option we have available?

Using the html links (rather than relative paths within the github repo) also complicates building--and checking--the website locally before submitting a PR. The links are only clickable after the PR is merged. 🙈