project-schema.json: add policyAlignment object and codelist

[odscjen]

Related issues

closes #410

Description

Merge checklist

• Log your changes

If there are changes to project-schema.json or project-package-schema.json:

• Update the examples:
  • docs/examples/example.json
  • docs/examples/blank.json
• Run ./manage.py pre-commit to update docs/_static/i8n.csv

If you added a new definition to the schema, run ./manage.py pre-commit.

If you added a new codelist:

• Add an entry to docs/reference/codelists.md

[duncandewhurst]

I added one commit to stop lint from URL-encoding {{version}} and {{lang}} placeholders in URLs. I can respond to any review comments from James on that change.

[duncandewhurst]

Ah, ignore my previous comment. I've reverted the commit because we should be using relative links in sustainability.yaml in any case.

[duncandewhurst]

I've merged 0.9-dev (including #428) so the build is passing now.