Add abbreviations for department and agency to dashboard output.

The designs for the services page include this information as part of the list, so it needs to be included in the dashboard jsons.
Merge pull request #446 from alphagov/feature/high-volume-department-abbrs

Add abbreviations for department and agency to dashboard output.
Ensure "Improve this dashboard" text is on all dashboards.
Add "Improve this dashboard" link to all dashboards.

Included ammends from latest spreadsheet export.
Fix to other-notes in dashboard footers.
Other notes is now in the correct dashboard field.