In order to have more control over the nodes subnets we expect instead
of relying on static configuration option it's better to have
flexibility. This commit introduces NodesSubnetsDriver model that will
allow writing more complicated drivers providing the
worker_nodes_subnets setting.
A use case in mind is to use OpenShift Machine Custom Resources in order
to discover subnets the nodes are using.
Change-Id: I0eb5d9ad50895151967c23d3ad6d1237cc4d9667
abc39b0e68