Include _internal/schema template to header

layouts/partials/header.html

@@ -18,6 +18,7 @@
 		{{ printf `<link rel="%s" type="%s" href="%s" title="%s" />` .Rel .MediaType.Type .Permalink $.Site.Title | safeHTML }}
 	{{ end -}}
 
+	{{- template "_internal/schema.html" . -}}
 	{{- template "_internal/opengraph.html" . -}}
 	{{- template "_internal/twitter_cards.html" . -}}
 	<link href='https://fonts.googleapis.com/css?family=Playfair+Display:700' rel='stylesheet' type='text/css'>