Avoid errors when reloading in dev mode

using a qualified class name avoids intermittent errors when using this
model in the app in development mode.
Remove unused features from SpecialistDocumentEdition

we copied a lot of unneccessary functionality from the mainstream
Edition. This strips it down to just what we need.
Merge pull request #132 from alphagov/cleanup-specialist-document-edition

Cleanup specialist document edition