Add permission

curl -s -H 'Authorization: Bearer <your API token>' -X POST \
  'https://coda.io/apis/v1/docs/<doc ID>/acl/permissions' \
  -d '{"access": "write", "principal": {"type": "email", "email": "foo@bar.com"}}'
# => Grant 'foo@bar.com' write access to the doc and send a share notification email