Use absolute_url filter for canonical and og:url

Author: khaledhosny

_includes/head.html

@@ -10,8 +10,8 @@
 {% if include.description %}
 <meta        name="description" content="{{ include.description | strip_html | strip }}">
 <meta property="og:description" content="{{ include.description | strip_html | strip }}">
-<link      rel="canonical" href="{{ site.url }}{{ page.url }}">
-<meta property="og:url" content="{{ site.url }}{{ page.url }}">
+<link      rel="canonical" href="{{ page.url | absolute_url }}">
+<meta property="og:url" content="{{ page.url | absolute_url }}">
 <meta property="og:site_name" content="{{ include.site_name }}">
 <meta property="og:image" content="{{ include.og_image }}">
 {% endif %}