Implement namespace cleanup for new DVR namespaces

DVR introduces a new namespace type called snat-<router_id>.  These
namespaces are not properly cleaned up when found stale after an agent
restart.  This patch fixes that.

Change-Id: I0d8b83e0b7838957742e72aa2f42b15e0ca67f04
Partially-implements: blueprint neutron-ovs-dvr
Cisco N1kv plugin to send subtype on network profile creation

Make sure that the cisco n1kv neutron plugin sends the sub_type too
when a overlay network profile is created

Change-Id: I37e63131039077fa80a28fe725c09f0307acc2ea
Closes-Bug: 1357125
Merge "Cisco N1kv plugin to send subtype on network profile creation"
Merge "Implement namespace cleanup for new DVR namespaces"