Support JSON-LD as document linked data container

[halindrome]

Annotating with RDFa is one way to capture semantic data in a document. Another is to rely upon JSON-LD. Both are aggressively indexed by the various search and knowledge engines. Building a JSON-LD context for W3C specs that relies upon some W3C vocabulary terms and then Schema.org for the rest would result in greater uptake.

[marcoscaceres]

This seems outside the scope of the project. ReSpec already annotates stuff with json-ld and search engines already find specs easily.