this is a UX improvement, always return a 404 not found when subject do not have any access on the resource
but returns an explicit 403 forbidden is subject try a forbidden action on a resourse it can read
regarding performance, the role is already in cache for the second call with read perm
automatically create default Calendar and default addressbook per user
(no creation if user already have a such resource)
default name are "Personal"
this is using the user's life cycle like does the drives
answers to issue #545
Edouard Vanbelle