Update RefWorks export to use form based approach

[mejackreed]

Current link callback to RefWorks seems to break on text that includes diacritics. We have resolved this by moving towards the form based approach (same as Vufind) in SearchWorks: sul-dlss/SearchWorks#2066

We would also want to make export_as_refworks_marc_txt a public method to do this.

[barmintor]

RE: export_as_refworks_marc_txt as public method:
I think the Blacklight API intention is to have clients call doc.export_as(:refworks_marc_txt). It looks like that would work in the SearchWorks example you sent - am I understanding that snippet correctly?

[barmintor]

The only place I'm seeing this kind of behavior is in bookmarks, unless it's Blacklight linking back to export formats. Is that link configurable over there?