SAML: Fix logout.
SAML: Fix logout.

xibosignage/xibo-cms,xibosignage/xibo-cms,alexharrington/xibo-cms,alexharrington/xibo-cms,alexharrington/xibo-cms,dasgarner/xibo-cms,alexharrington/xibo-cms,dasgarner/xibo-cms,xibosignage/xibo-cms,dasgarner/xibo-cms,xibosignage/xibo-cms,alexharrington/xibo-cms,dasgarner/xibo-cms,xibosignage/xibo-cms,xibosignage/xibo-cms,dasgarner/xibo-cms,dasgarner/xibo-cms