Common code (Singleton)
Common code (Singleton)

Change-Id: Id321f825d0bcd500f74655cf59dd3b8cbfd5bfc1

Brocade-OpenSource/OpenStack-DNRM-Neutron,Brocade-OpenSource/OpenStack-DNRM-Neutron,Brocade-OpenSource/OpenStack-DNRM-Neutron