In Pike and later, the name_lower field in network_data.yaml can be
re-defined to contain a custom network name. When this is done the
ServiceNetMap field must be overridden to reflect the new name in all
places. This changes adds a new optional field to network_data.yaml
that should be set to the original default name_lower value.
ServiceNetMap will then be automatically updated and will not need
to be overridden.
This also fixes the VipPort naming for the StorageManagement network
to not use a static value.
Change-Id: I8a238038122288899cef49faf38ea2c2ffc2176b