Add link to JSON-LD data dump

[kouralex]

At the moment, Skosmos does not list JSON-LD version of the vocabulary (its data dump) on the vocabulary page, even though it may be declared and downloaded via the REST API.

The culprit seems to be here (see the code below); there is no treatment for JSON-LD.

Skosmos/view/vocab-shared.twig

Lines 58 to 76 in 91a30e5

	<div class="download-links">
	<span class="versal">{% trans %}Download this vocabulary:{% endtrans %}
	{% if 'application/rdf+xml' in vocab.config.dataURLs|keys %}
	<a href="rest/v1/{{ request.vocabid }}/data?format=application/rdf%2Bxml">RDF/XML</a>
	{% endif %}
	{% if 'text/turtle' in vocab.config.dataURLs|keys %}
	<a href="rest/v1/{{ request.vocabid }}/data?format=text/turtle">TURTLE</a>
	{% endif %}
	{% if 'application/marcxml+xml' in vocab.config.dataURLs|keys %}
	{% if vocab.config.dataURLs['application/marcxml+xml'] is iterable %}
	{% for key, values in vocab.config.dataURLs['application/marcxml+xml'] %}
	<a href="rest/v1/{{ request.vocabid }}/data?format=application/marcxml%2Bxml&lang={{key}}">MARCXML/{{ key | lang_name(request.lang) }}</a>
	{% endfor %}
	{% else %}
	<a href="rest/v1/{{ request.vocabid }}/data?format=application/marcxml%2Bxml">MARCXML</a>
	{% endif %}
	{% endif %}
	</span>
	</div>

As application/ld+json is already in supported formats, no other changes are required. EasyRdf interprets .jsonld files as such so no dc:format declaration is required (just tested).