Networking configuration in kickstart templates

extracted from https://github.com/theforeman/foreman/pull/1565
If we broke it by configuring these scripts, it will be probably broken after reboot anyway? I think we should get other networks configured so users can use them in later in kickstart template. Also first puppet run would upload facts like IP addresses that interfaces got from external DHCP servers. Therefore other hosts that may wait on this information does not have to wait for first puppet run after rebooting.