Put upper constraint on ncclient version to prevent breakages
Put upper constraint on ncclient version to prevent breakages

ncclient version 0.6.2 just released and broke all our ASR CI, so
instead of picking up new ncclient versions we'll set a max version
which we can increase as required.

Change-Id: I08a60251078dea290f638f061bb96178e692a95c

noironetworks/networking-cisco,openstack/networking-cisco,noironetworks/networking-cisco,openstack/networking-cisco