gh-3: disable NetworkManger in rhel networks
gh-3: disable NetworkManger in rhel networks

Patch provided by Nicolas Belan

baby-gnu/addon-context-linux,fasrc/addon-context-linux,ungleich/addon-context-linux,OpenNebula/addon-context-linux,puppetmaster/addon-context-linux,fasrc/addon-context-linux,thomasalrin/addon-context-linux,puppetmaster/addon-context-linux,ungleich/addon-context-linux,baby-gnu/addon-context-linux,OpenNebula/addon-context-linux