Give Document formatters specific "kind"

Instead of being generic about how we register documents with panopticon give them an explicit "kind" which is stored with the PanopticonMapping as resource_type. In order to find these again we will need to change the PanopticonMapping#documents scope to pull all types of specialist-document.

While we are here lets also rename DocumentArtefactFormatter to a CmaCaseArtefactFormatter which is its correct name!
Remove legacy publishing for documents

Previously, we were doubling up on the contents of the details hash in
order to allow publishing to both the Finder API and Content API. This
commit removes the duplicated details hash.
Merge pull request #159 from alphagov/feature/bump-content-models-version

Allow new format types for specialist documents
Remove scopes from PanopticonMapping

The `manuals` scope was unused. The `documents` scope was only used by
the `all_document_ids` method. The only code using the
`all_document_ids` method was the `SpecialistDocumentRepository`.

Rather than getting the list of document ids from `PanopticonMapping` we
can use a `distinct` query against `SpecialistDocumentEdition`.
Remove unused dependency from SpecialistDocumentRepository

It no longer uses `panopticon_mappings` now that it gets the list of
document ids from `SpecialistDocumentEdition`.

Also swap the dependencies to using a hash style instead of ordered
arguments.
Merge pull request #160 from alphagov/remove-legacy-dual-publishing

Remove legacy publishing for documents
Merge pull request #161 from alphagov/remove-panopticon-mapping-scopes

Clean up PanopticonMapping and SpecialistDocumentRepository
Add AAIB Reports to Rummager on publish

In order to expose AAIB Reports in search, we need to send the documents
to Rummager when publishing.