[EP-tech] Add further division to record - even if not owner or editor

[Thomas Lauke]

Hi Roland,

following https://wiki.eprints.org/w/User_roles.pl 
a single privilege '+eprint/archive/edit' would allow this (assuming the edit-link is known, otherwise '+eprint/archive/details' should help), but enables the eprint modification in general ...!
Currently only the dataset, role and status are distinguished in privilege's specification :(

If you modify the workflow for a new role 'creator', you could be more specific ...!?

Hth
Thomas