migrate.md in ajax-datatables-rails-1.3.1

- old
+ new

@@ -1,5 +1,5 @@
-## To migrate from `v1.0.x` to `v1.3.0`
+## To migrate from `v1.x` to `v1.3.0`
 
 The *v1.3.0* version has some breaking changes :
 
 * `AjaxDatatablesRails.config.db_adapter=` is removed and is configured per datatable class now. It defaults to Rails DB adapter. (fixes [#364](https://github.com/jbox-web/ajax-datatables-rails/issues/364))
 