Bug 19349: Store record's creator and last modifier in record

Bug 19349: Store record's creator and last modifier in record

Test plan:
1. Run updatedatabase.pl
2. Set sysprefs MarcFieldForCreatorId, MarcFieldForCreatorName,
   MarcFieldForModifierId, MarcFieldForModifierName
3. Create a new biblio
4. Verify that the fields are correctly filled
5. Logout and login as another user
6. Modify the same biblio
7. Verify that only the fields for last modifier have been modified

Works perfectly.

Signed-off-by: Simon Pouchol <simon.pouchol@biblibre.com>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>