extend network api for hpb

At present, in many scenarios such as finance or government, customers use hierarchical port binding to break through 4K network. In addition, for security and privacy needs, customers need different providers for underlying segments of the networks, such as bussiness00 for business network or storage01 for storage network. The current neutron API for the network does not support specify the provider of the underlying segment. For this requirement, we need to extend the network API of neutron by adding a field for the provider that specifies the underlying segment.
For example:
ml2_conf.ini conf like these:
cluster1: network_vlan_ranges=storage00:1:2000,busness00:2001:4094
cluster2: network_vlan_ranges=storage01:2001:4094,busness01:1:2000
We can use the field to specify the provider prefix like "storage" for the bottom segment of storage-network.