Remove Manual Presenters

With moving Manuals to the content store they are no longer sent to the Content API. This change had a knock on effect of breaking the static seeder because after it had a page, it loaded it from the Content API.
The presenter is decided from the format which relied on certain information being present in order to format it like a Manual or a ManualChangeHistory page. As this wasn't sent to the Content API, this would then 404.

This commit removes all the code differing Manuals and Manual Change History from a normal Artefact as all the information the seeder needs is present in this.