Add info about NVR
Add info about NVR

For rubygem spec files it is required to have the info about generated
NVR to successfully unpack gem. This patch adds a new global to spec
containing such information.

Change-Id: I297d00173621cb25923e49e15c75017a427323ca

openstack-packages/DLRN,openstack-packages/DLRN,openstack-packages/delorean,openstack-packages/delorean