Supporting provider networks including:
- Creating a base plugin for T & P plugins (separate from V)
- Moving some nsx-T code to the common plugin after stripping
it from v3 specific code
- Reusing the nsx-T DB table for keeping the provider network
configurations
- Support for vlan transparent
- Support for update network action
Also adding unit tests for provider networks and enabing tempest
tests for networks
Change-Id: I505ef65f2ee6bfba78dadff62c4c06463ebffff0
00134a8e31