This commit merges the nicira-l3support branch with master. This
effectively adds nicira nvp l3 support to master. The NiciraNVP Provider
can support the following services with this modification: Connectivity,
SourceNat, StaticNat and PortForwarding
Testing done:
Create, Delete network offerings with Nicira Element
Use Gui to add, modify, remove Nicira Element and Provider
Provision, deprovision SourceNat networks
Provision, deprovision Portforwarding and StaticNat rules
Tested with Nicira NVP release 2.1.0, 2.2.0 and 2.2.1 (2.2.x recommended)