*8537* More obvious Dataverse deposit consent, *8553* Allow external citation

Add data publishing options to suppfile form. Offer submitters the option of
treating suppfiles as supplementary (not published) or as data files, published
in Dataverse.

Add external data citation field, from article metadata, to allow add/edit of
citation at point of deposit (all data publishing options available in the same
place).
*8537* More obvious Dataverse deposit consent, *8553* Allow external citation

Revised form handling for suppfile options: treat uploaded file as supplementary
or deposit in Dataverse. Offer external data citation field, stored in
article-level metadata, in data publishing options presented in suppfile.
Error deleting suppfiles in incomplete submissions that had been marked for Dataverse deposit
 *8537* More obvious Dataverse deposit consent, *8553* Allow external citation

Add form validator to suppfiles to warn when Dataverse deposit selected but no suppfile has been uploaded