fixing disqus comment logic

_includes/disqus.html

@@ -7,7 +7,7 @@
      *  LEARN WHY DEFINING THESE VARIABLES IS IMPORTANT: https://disqus.com/admin/universalcode/#configuration-variables
      */
     var disqus_config = function () {
-        this.page.url = "{{page.url}}";  // Replace PAGE_URL with your page's canonical URL variable
+        this.page.url = "{{site.url}}{{page.url}}";  // Replace PAGE_URL with your page's canonical URL variable
         this.page.identifier = "{{page.permalink}}"; // Replace PAGE_IDENTIFIER with your page's unique identifier variable
     };
     (function() {  // REQUIRED CONFIGURATION VARIABLE: EDIT THE SHORTNAME BELOW