Use the 'base' image as the base for the 'node' image
Use the 'base' image as the base for the 'node' image

Currently the 'node' image uses the CentOS 7 image as its base, and then
installs the oVirt release RPM and all the components required by the
node. This patch changes it so that it uses the recently introduced
'base' image, which already contains the release RPM.

Change-Id: I6b387b62032f0409de0bc6124c03fb6d12593d5f
Signed-off-by: Juan Hernandez <59e5b8140de97cc91c3fb6c5342dce948469af8c@redhat.com>

jhernand/ovirt-containers,jhernand/ovirt-containers