Add more detailed faults to better indicate the reason of a failed operation

[danbim]

E.g. when talking to the reservation system (RS) the RS will throw a RSException if the user is not logged in anymore because his session timed out.

[danbim]

Also raise a fault if the user is not authorized. The fault should indicate to which node URNs the user is not authorized and an error message, i.e. basically it should contain the authorization response from SNAA.