Remove old docs

These have been here for a long while now.

I've kept a branch `old-docs` that points to before this commit, for preservation.

Author: chenglou

.npmignore

@@ -16,7 +16,6 @@
 docs/*
 docs/docson/*
 !docs/docson/build-schema.json
-site/
 .vscode/
 .github/
 odoc_gen