Display new metadata fields

[virginiacc]

Addresses internal ticket 1057.

Displays the fields added in #77 on the front end.

Additions

• Add an h4 formatting option for the additional_notes field
• Show the Additional Notes expandable when additional_notes field is populated
• Display last updated messages containing the additional_notes_last_modified and interpret_fields_last_modified values when they are populated
• Add new date formatting option for the last updated dates
• Add tests for new metadata output and new date format
• Update evaluator metadata type to reflect new fields

Testing

1. PR checks should pass
2. To test manually, check out branch and navigate to an evaluator page.
   • Note that the Additional notes expandable is not displayed since there is no content for that metadata field.
   • Use the admin link in the How to evaluate expandable and add content for the additional notes and one other metadata field.
   • Note that the Additional notes expandable is displayed with the content added for that field.
   • Note that last modified dates are shown in both the How to evaluate and Additional notes expandables.

Screenshots