Implement read of IPv4 network configuration
Implement read of IPv4 network configuration

Use standard IPv4 related configuration parameters
to fetch relevant data for basic network connectivity.

Change-Id: I2b93da5be0196ff5f15e240ed8f8e0fd819ddd54

openstack/pyghmi,stackforge/pyghmi,openstack/pyghmi,benoit-canet/pyghmi