Add Open Graph metadata.

Fixes #9

Author: mblayman

_includes/head.html

@@ -5,6 +5,7 @@
     <meta name="viewport" content="width=device-width">
     <meta name="description" content="{{ site.description }}">
     <link rel="canonical" href="{{ page.url | replace:'index.html','' | prepend: site.baseurl | prepend: site.url }}">
+    {% include og.html %}
 
     <link rel="icon" type="image/x-icon" href="/img/favicon.ico">
 

_includes/og.html

@@ -0,0 +1,7 @@
+<meta property="og:type" content="website" />
+<meta property="og:title" content="{{ site.title }}" />
+<meta property="og:url" content="{{ site.url }}" />
+<meta property="og:image:url" content="{{ site.url }}{% link img/logos/pythonfrederick.jpg %}" />
+<meta property="og:image:width" content="600" />
+<meta property="og:image:height" content="596" />
+<meta property="og:description" content="{{ site.description }}" />