Modify code to store multiple contributors as pipe separated values for the same paper ID

[valearna]

This would make the table work as all the other afp tables and avoid storing multiple rows for the same paper

[draciti]

this is important. Besides multiple authors we need to be able to capture author and curator (when curator goes in and validates the submission)

[draciti]

We already allow in the code to store multiple contributors. Need to define the curator workflow for curator validation