Use virtual ip for OS services

VIP should be used when pointing an OS service to
another OS service in config files (most typical is
setting Keystone's host IP, but also Glance and Netron
host needs to be set in Nova config file).

Change-Id: Id91e6ef2747981f17a43afd279d4eebaad01fe4d
Merge "Use virtual ip for OS services"