fix search bar

Author: hamishwillee

_includes/search_box_scripts.html

@@ -6,7 +6,7 @@
 <script language="Javascript" type="text/javascript">
   function my_search_google()
   {
-    var query = document.getElementById("my-google-search").value;
+    var query = document.getElementById("searchbox").value;
     window.open("http://google.com/search?q=" + query
 	+ "%20site:" + "{{ site.url }}");
   }