471 environmental measures

[odscjen]

Related issues

closes #471

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

[neelima-j]

• 'environmentalMeasures' to be added to documentType
• Other changes suggested to match issue discussion.

[odscjen]

@jpmckinney this should be the final PR for changes to 0.9.4. Once this is merged we can merge 0.9-dev into 0.9 and then make a start on the Spanish translation of the new bits.

[jpmckinney]

Just a few suggestions to make the codelist and schema easier to read.

[odscjen]

Thanks @jpmckinney I've made those updates, is this ok to merge now?