Allow specifying ssh key file for compute nodes and network controller

Having equal host-list output and host-add descriptor
Ignore console input error when launching as a service
Register network error upon dhcp controller error
fix configure-dhcp-server-UBUNTU16.0.4.sh help error

Change-Id: I30b5af3b25d7f2f86a75a4502af10b5e16fd3202
Signed-off-by: tierno <alfonso.tiernosepulveda@telefonica.com>