Update Vnet::NodeApi::LeasePolicy.allocate_ip
Update Vnet::NodeApi::IpLease.create so as not to dispatch events related to interface if an ip_lease does not belongs to any interface.

related to the interface
Allow ip_leases.interface_id and ip_leases.mac_lease_id to be null
Update lease policy spec
Fix a broken association
Update Vnet::NodeApi::LeasePolicy.allocate_ip to add the created ip_lease to ip_lease_containers
Remove trailing whitespace
Add support for logger
Add option `ip_container_uuid` to Vnet::NodeApi::LeasePolicy.allocate_ip
Refactor allocate_ip
Add association dependencies
Add POST lease_policies/:uuid/ip_leases
Add association_dependencies
Fix association name issue
Change the order of tables
Add `label` fields to identify the owner
Change an argument of Vnet::NodeApi::LeasePolicy.allocate_ip
Change a parameter of lease_policies/:uuid/ip_leases
Fix a wrong param definition
Change a parameter name