* origin/pr/163:
init/functions: better not use ipcalc which is not present on minimal distro
Handle errors for non-present ip gateways
Better use '-z' and '-n' for readibility
init/functions: handle non-present /qubes-mac qubesdb and check if iface exists
configure_network: use classical function parsing
Handle legacy non-present /qubes-mac qubesdb entry
Refactor and handle new network qubesdb configuration
