Instead of forcing the name of the services in the service catalog to
match auth_name and auth_name_v3, this allows the ability to explicitly
set the service names, separately from auth_name and auth_name_v3.
If service_name or service_name_v3 is not specified, their values
default to the value of auth_name and auth_name_v3, respectively
(which maintains the current behavior.)
Closes-bug: #1359755
Change-Id: Ie34099d6f9746ce883d711a27b9d93613924c3ee