Mm 3.0 feedback response

[mrshll1001]

Related issues

• fixes #398
• fixes #404
• fixes #406

Description

This PR represents some small fixes to address points raised in the linked issues. Further commits may be added based on other issues.

Merge checklist

• [ ] Update the changelog

If you have edited any schema files:

• [x] Run hsds_schema.py to update datapackage.json and example files
• [ ] Update the logical model page if relevant