Improper handling of titles in captions

[Klortho]

This corresponds to wpoa/OA-signalling#73.

The problem is in the way that titles inside captions are being rendered.

• PMC3760134
• Source from FTP site
• To see what it looks like in PMC
• The way it looks in rendered MediaWiki wikitext, on WikiSource

The source XML markup looks like this:

      <supplementary-material id="zookeys.324.5827-treatment3" content-type="local-data">
        <caption>
          <title>XML Treatment for <named-content content-type="genus">Bassaricyon</named-content>
            <named-content content-type="species">neblina</named-content>
            <named-content content-type="subspecies">osborni</named-content>
          </title>
        </caption>
        <media xlink:href="zookeys.324.5827-treatment3.xml" mimetype="text" mime-subtype="xml"/>
      </supplementary-material>

It's not clear to me that these should be turned into headers. In PMC they are not.

[Klortho]

Rather than attempt any complicated changes in logic, which might break things for other articles, I just fixed these as headers.