[FIX] web: when in monodb mode, allow admin routes to be called without being logged in.

This restore old behavior lost by commit 3882 chs@openerp.com-20131118172304-a54lgu6dm865k8xf
Merge branch 'master' of bzr::lp:~openerp/openerp-web/saas-2 into ocb-saas-2