hudmol/archivesspace — pull request #156 by payten (2012-11-27 05:55:20+00:00)
Title: [Delivers #36863945] Remove 'expression' as date_type and setup as a field parallel to other date_type fields

- Remove 'expression' as date_type and setup as a field parallel to other date_type fields
- Date 'expression' is optional, but if provided, a date_type becomes optional.
- Fix linked records throwing an exception if 'ref' was nil. Also refactored the linker widget to set an ID on the element, to support error messages.