Add plugin config file to /etc/default/neutron-server

Debian platforms uses /etc/default/neutron-server to tell
neutron-server service which plugin configuration file to load.

Configure it.

Change-Id: I0638d2584ad327ae1ed77f672d5efb1c28064aa2
Closes-bug: #1357431
New manifest file to deploy Cisco N1KV-VEM

Background on 'N1KV-VEM’: It is the host-side component of N1KV
implementing the notion of Virtual Ports for VM Interfaces and also
handling the VM data-traffic. VEM is implemented as a couple of
user-space processes and also has a KLM for efficient data-path
switching.

VEM manifests does: setting up the Config-File for VEM service,
Starting VEM service and finally adding physical ports (along with
port-profile) to the VEM

Change-Id: Ibc8f1c4d2d743589e452ae6d1d87b5bfa123bc3a
Add ability to manage Neutron ML2 plugin package state

Introduce the package_ensure parameter to add the ability
to manage Neutron ML2 plugin package state.

Closes-bug: #1355370
Change-Id: I3bf6ed68015c13cf61db1b43dfbf4fd3c845d00f
Merge "Add ability to manage Neutron ML2 plugin package state"