add application/ld+json jsonld

application/ld+json  jsonld

- What: JSON-LD JSON for Linking Data - http://json-ld.org
- Why:  JSON-LD is in the final stages of standardization at W3C (http://json-ld.org/spec/latest/json-ld/). It was adopted by Google, Yahoo, Yandex, and Microsoft for use in [schema.org](http://schema.org)