add the missing querystring of the URL

For the current version, the query string is missing in splash page.
This bug was induced by the commit ca80cbb, which contains only some
part of patch form wifidog: http://dev.wifidog.org/changeset/1239 .
add the missing querystring of the URL

For the current version, the query string is missing in splash page.
This bug was induced by the commit ca80cbb, which contains only some
part of patch form wifidog: http://dev.wifidog.org/changeset/1239 .