Allow map_replace substitution of network names

Allow map_replace substitution of network names

To allow per-node data such as bind_ip's to move into the
composable services templates, we do a value substitution
on the config settings hiera map, where e.g internal_api
will be replaced with the NetIpMap IP assigned to that.

To enable subnet/uri lookup via the same method, we add
all the subnet/uri mappings to the main net_ip_map output.

Change-Id: I7850d4dc8bf4db5f7ac6a6b53c1d900b561b4580