Staff client login screen has a separate CSS file which wasn't
included in the original changes for Bug 6865. This caused a 404
error (missing background image).
Signed-off-by: Jared Camins-Esakov <jcamins@cpbibliography.com>
Tested in Chrome, FF, Safari, and IE8.
Signed-off-by: Paul Poulain <paul.poulain@biblibre.com>