Add libraries page to the docs

[huijing]

Closes #263

This PR adds a page to the documentation's Resource section for libraries. It lists the libraries in a table form, with fields that show which version of the specification the libraries are compatible with and a repository link.

🎩 Top-hatting instructions (i.e. human testing that things are not broken)

1. Pull down this branch
2. Navigate to http://localhost:3000/docs/libraries and check that the page is rendering correctly (or you could probably use the deploy preview since we turned that on ¯\_(ツ)_/¯)

[netlify[bot]]

✅ Deploy Preview for webmonetization-preview ready!

Name	Link
🔨 Latest commit	871d74713b12244f3776c3a692eb183dfc6e92c1
🔍 Latest deploy log	https://app.netlify.com/sites/webmonetization-preview/deploys/64aeacdcf58f650008ea2126
😎 Deploy Preview	https://deploy-preview-347--webmonetization-preview.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.