Access to Memory (AtoM)

Related to the following post in the User forum (2018-07-11) and issue #4324:

• https://groups.google.com/d/msg/ica-atom-users/Zo0DX8N8msk/dTGu-7DqCwAJ

• Create a new repository record, FOO
• Create a new authority record, also named FOO
• Create a new description, and try to link the FOO authority record
• Navigate to an existing authority record, and try to create a relationship with FOO

• Both FOO the authority record and FOO the repository record appear in authority record drop-downs and autocompletes
• User has no way of distinguishing the repository record from the authority record when names are the same (which is a fairly common use case - for example, it exists in the AtoM demo datA)

• Repository records should not appear in authority record autocompletes
• Both authority records and descriptions have their own way of linking to repository records; these should be used instead

Notes

See #4324 for previous context. It appears in that case, the solution was just to resolve the 404 error

This is likely occurring because in AtoM's data model, a repository is just a special type of actor. Prior to 2.4 there was no other way in the user interface to create a relationship between an actor and a repository. However, in 2.4 a field to link an actor to a repo as its maintainer has been added. Because of this, I think we should no longer display repositories in actor autocompletes, if it's possible to filter them out.