welcome: Fix issue where project browsing is cancelled.

Re-enable the action buttons when we get the file chooser callback
in case the user did not select a path to open.
Patch from Vincent Torri - thanks.

src/bin/screens/edi_welcome.c

@@ -97,6 +97,8 @@ _edi_welcome_project_chosen_cb(void *data,
                        void *event_info)
 {
    evas_object_del(data);
+   elm_object_disabled_set(_edi_open_button, EINA_FALSE);
+   elm_object_disabled_set(_edi_create_button, EINA_FALSE);
 
    if (event_info)
      {