Function to migrate all unused networks of project

List all networks in the project via Neutron API and filter out those already
picked for migration as a server dependency. Prepare migration flow and add it
to the main project migration flow.
Subnet migration functions for project workload

Subnets are identified by the network id.
Merge remote-tracking branch 'origin/master' into project-networks
Network migration in project workload migration flow

Migrate networks that belong to the project but no servers are connected to
that network.
Project networks migration for nova-network

Add plugin to support both neutron and nova networks for project migration.
Add function to migrate nova networks for the given project.
Merge remote-tracking branch 'origin/master' into project-networks
Restore floating ips for server after migration

Plugin to restore floating ips tied to 'network_manager' config parameter.
Migrate unused networks for project workload