kuryr-libnetwork use neutron qos for containers

Support Neutron has qos[1] feature in kuryr-libnetwork. Neutron support both network level and port level qos. currently, the idea is use libnetwork network Options to pass qos info from libnetwork to neutron for network level qos. for port level qos, since libnetwork do not pass Options , so still TBD now.

Example:
$ sudo docker network create --driver=kuryr --ipam-driver=kuryr \
              --subnet 10.0.0.0/16 --gateway 10.0.0.1 --ip-range 10.0.0.0/24 \
              -o neutron.qos.bw_limiter.max_kbps=200 -o neutron.qos.bw_limiter.max_burst_kbps=2000 \
              foo

Then kuryr can create network bind with bandwidth-limit qos policy, for other neutron qos policy, it is similiar.

[1] http://docs.openstack.org/newton/networking-guide/config-qos.html