Link prefix to DOI when it forms a URL

[adunning]

Certain styles (e.g. MHRA, APA) write the DOI prefix as a URL, putting http://dx.doi.org/ or http://doi.org/ (as opposed to Chicago, which simply calls for doi:). This is not written as part of a link when it is run through pandoc-citeproc. If we take this as an example:

pandoc -F pandoc-citeproc << EOT

---
references:
- DOI: 10.1017/CBO9781139923279
  id: wakelin:2014scribal
csl: modern-humanities-research-association-author-date.csl
...

@wakelin:2014scribal

EOT

This is the result:

<p><span class="citation">([n.d.])</span></p>
<div class="references">
<p>[n.d.]. &lt;http://dx.doi.org/<a href="http://dx.doi.org/10.1017/CBO9781139923279">10.1017/CBO9781139923279</a>&gt;</p>
</div>

But this would be better:

<p><span class="citation">([n.d.])</span></p>
<div class="references">
<p>[n.d.]. &lt;<a href="http://dx.doi.org/10.1017/CBO9781139923279">http://dx.doi.org/10.1017/CBO9781139923279</a>&gt;</p>
</div>

I asked about this at citation-style-language/styles#1428, where it was thought that citeproc variants should detect where the prefix is a URL rather than changing the method for writing this in CSL.

[adunning]

Also, it might be worth pointing out that the DOI Foundation states that http://doi.org/ is now the preferred resolver.

[adunning]

Thank you!