Map neutron_management_network to net_id in CLI

The JSON representation of a cluster uses neutron_management_network
as a property name. The CLI allows for JSON injest, which is then
translated into a ClusterManager.create call. The injest maps property
names to parameter names to ClusterManager.create. This works in all
cases except neutron_management_network, which is the net_id parameter
to create.

To address this, the CLI accepts neutron_management_network and maps
it to the net_id parameter.

Change-Id: I69799d0108740f0e79c82e45714fd946e9a2a4b0
Closes-bug: #1273500