Add support for script type "application/ld+json"

[biasso]

The media type "application/ld+json" for <script> tag should be supported.

This is what I expect:

<script type="application/ld+json">
  {
    "@context": "http://schema.org",
    "@type": "Person",
    "name": "John Doe",
    "address": {
      "@type": "PostalAddress",
      "addressLocality": "Wonderland"
    }
  }
</script>

Instead, this is what I get:

<script type="application/ld+json">
  { "@context": "http://schema.org", "@type": "Person", "name": "John Doe", "address": { "@type": "PostalAddress", "addressLocality": "Wonderland" } }
</script>

[bitwiseman]

Great! Just add some tests and submit a pull request!