Stop JS from rendering outside of head tag

When I moved to the govuk_admin_template I accidentally left some things outside of content_for tags which meant that there were a whole bunch of script tags at the top of the page before the <head> this caused ie^ and 7 to get very confused, naturally.
Merge pull request #143 from alphagov/fix-ie-error

Stop JS from rendering outside of head tag
Send nulls instead of empty strings to FinderAPI
Merge pull request #144 from alphagov/fix-finder-api-nulls

Send nulls instead of empty strings to FinderAPI
Tag repository KeyError to distinguish from regular KeyErrors

This is a quick fix that allows us to retain use of exceptions for
flow control.
Merge pull request #145 from alphagov/custom-not-found-error

Tag repository KeyError to distinguish from regular KeyErrors
Index CMA cases in Rummager on publish

Also remove them from Rummager when they're withdrawn.
Remove dependency on SpecialistDocumentAttachmentProcessor
Add spec for CmaCaseIndexableFormatter
Stub Rummager requests in cukes