Node-specific VM configuration files

The three files in this changeset define for each node (controller,
network, compute) the networks it is attached to, the last octet
of its IP addresses, and any port forwardings from the host system
to the VM.

Partial-Bug: 1312764
Implements: blueprint openstack-training-labs
Change-Id: I3dece1457ba78cd5eb7f3a455705b510cac0abe8
Merge "Node-specific VM configuration files"