Optionally disable to back-call to the OwnCloud logout() method. This
is beneficial in conjunction with my dokuwikiembed OwnCloud-App. In that
case DokuWiki is embedded in to an owncloud and the logout-call can
actually lead to an infinite recursion and is also unneccessary, because
the logout-hook from OC already calls the logout-method from DW in order
to withdraw the DW credentials.