Improve persian string ordering

It performs better when we have also non-Persian strings. It puts Persian strings before non-Persian strings.

sorting/persian.js

@@ -6,6 +6,7 @@
  *  @name Persian
  *  @summary Sort Persian strings alphabetically
  *  @author [Afshin Mehrabani](http://www.afshinblog.com/)
+ *  @author [Mohammad Javad Naderi](https://github.com/mjnaderi)
  *
  *  @example
  *    $('#example').dataTable( {
@@ -26,25 +27,27 @@ function GetUniCode(source) {
         var i, index;
         for (i = 0; i < source.length; i++) {
             //Check and fix IE indexOf bug
-		if (!Array.indexOf) {
+            if (!Array.indexOf)
                 index = jQuery.inArray(source.charAt(i), persianSort);
-		}else{
+            else
                 index = persianSort.indexOf(source.charAt(i));
-		}
-		if (index < 0) {
-			index = source.charCodeAt(i);
-		}
-		if (index < 10) {
+
+            if (index < 0)
+                index = source.charCodeAt(i) + 40;
+
+            if (index < 10)
+                index = '00' + index;
+            else if (index < 100)
                 index = '0' + index;
-		}
-		result += '00' + index;
+
+            result += index;
         }
         return 'a' + result;
     }
 
     jQuery.extend(jQuery.fn.dataTableExt.oSort, {
         "pstring-pre": function (a) {
-		return GetUniCode(a.toLowerCase());
+            return GetUniCode($(a.toLowerCase()).text());
         },
 
         "pstring-asc": function (a, b) {