Remove code relating to deduplication

Deduplication has been moved to the `support-api`.
Merge pull request #208 from alphagov/remove-deduplication-code

Remove code relating to deduplication
Bump "govuk_admin_template" to 1.1.2

This picks up Bootstrap 3.2 and latest framework improvements.
Use 'input-md-X' CSS classes from "govuk_admin_template"
Remove endpoint for creating long-form feedback

This endpoint has now been moved to the 'support-api'; long-form feedback is now
read-only in this app.
Remove endpoint for creating problem reports

This endpoint has been moved to the 'support-api' app.
Merge pull request #209 from alphagov/bump-govuk_admin_template

Bump "govuk_admin_template"
Merge pull request #210 from alphagov/remove-unused-endpoints

Remove unused endpoints