apps.cradmin_imagearchive: Basic reusable image archive app.
apps.cradmin_imagearchive: Some more work on the imagearchive app.
viewhelpers.crudbase: Handle roleid_field on save instead of has hidden fields.

Adds support for GenericForeignKey fields too.
apps.cradmin_imagearchive: Working but unsyled and no previews.
apps.cradmin_imagearchive: Tests for the update view.