Use ErrorWrapper in CopyrightTransfer
Minor refactoring in CopyrightTransfer
Extract User to /models/authentication
Change USERS column names, enforce USERS table creation if needed
Map USERS table to case class
Extract some boilerplate to DatabaseSessionWrapper
Move USERS table auto-creation to DatabaseSessionWrapper
Implement Copyrights table class (still not wired to Copyright case class)
Extract USERS table name to a constant
Implement CopyrightTransferRequests table class
Implement CorrespondingAuthors table class
Implement Contributions table class