DRY: Basic Model Concerns
New concern: Protectable
New Entity Concern: Creatable
Refactoring towards Repository Concern
Refactored away one more method
Attachments uses Repository Concern
Refactored away Attachments#attachment_key
DRY: Both repositories use .find from Concern
Moved #download from Repository to Concern
Moved #destroy from Repository to Concern
Extracted all Repository functions into Concerns