Update sorting so it can support internationalization, see http://stackoverflow.com/a/26295229/759452

Fix as mentioned in #4811 (comment)

Author: 0xadri

src/js/core/services/rowSorter.js

@@ -206,7 +206,7 @@ module.service('rowSorter', ['$parse', 'uiGridConstants', function ($parse, uiGr
       var strA = a.toString().toLowerCase(),
           strB = b.toString().toLowerCase();
 
-      return strA === strB ? 0 : (strA < strB ? -1 : 1);
+      return strA === strB ? 0 : strA.localeCompare(strB);
     }
   };