Pubstwo 995

This is a partial implementation; I've only tested it for persistence of biblio data with the existing pub (#2).
It depends on the service implementation. So far, the pubs services all give appropriate status codes. When I wrote that I was probably thinking of OGC services, which pretty much always return 200's, and expect the client to detect error messages in the "successful" response. It might not be necessary now, but I think it's ok to keep around as cheap insurance for when our web service implementations change. What do you think?