Handle the more restrictive singular/multiple fields

Conflicts:
	app/views/records/edit_fields/_default.html.erb
	app/views/records/edit_fields/_description.html.erb
	app/views/records/edit_fields/_rights.html.erb
	spec/views/catalog/index.html.erb_spec.rb
	sufia-models/app/models/concerns/sufia/generic_file/web_form.rb
Adjust string/arrayness of properties
Set multiple to false for on_behalf_of and proxy_depositor
Remove audit logic from the view
This correctly causes an error which should be resolved by #722
Fixes #734
Update to hydra-jetty 8.1.1
Using new versions interface

ActiveFedora::Versionable now uses objects to represent each version of
a resource.
Bump to active-fedora beta 6
Run audits on ResourceVersion instead of uris

This brings Sufia’s audit process inline with ActiveFedora’s
updated version interface.
Check for uniqueness of the field by using the existing class method