Add JSON-LD for EIPS (#2796)

* Add JSON-LD for EIPS

* Update eip.html

_layouts/eip.html

@@ -42,3 +42,22 @@ <h1 class="page-heading">
   {{ content }}
 
 </div>
+{% comment %}
+Article schema specification:
+https://schema.org/Article
+{% endcomment %}
+<script type="application/ld+json">
+  {
+    "@context": "http://schema.org",
+    "@type": "Article",
+    "author": "{% include authorlist.html authors=page.author %}",
+    "name": "EIP-{{ page.eip | xml_escape }}: {{ page.title | xml_escape }}{% if page.status == "Draft" or page.status == "Last Call" %} [DRAFT]{% endif %}",
+    "dateCreated": "{{ page.created | date: "%Y-%m-%d" }}",
+{% if page["discussions-to"] != undefined %}
+    "discussionUrl": "{{ page["discussions-to"] | uri_escape }}",
+{% endif %}    
+    "inLanguage": "en-US",
+    "license": "#copyright",
+    "copyrightYear": "{{ page.created | date: "%Y" }}"
+  }
+</script>