Description of problem:

When changing NIC configuration from initramfs in tui is broken.

Version-Release number of selected component (if applicable):

RHEL-7.4-20170315.n.1

How reproducible:

Always

A) dhcp (initramfs) -> static (tui)

Steps to Reproduce:

1. Run text network installation with one NIC, activated with dhcp in initramfs (no boot option or ip=ens3:dhcp)
2. In tui change the configuration to static with applying it in installer environment (check 8) [x] Apply configuration in installer)

Actual results:
The configuration is not applied, there is BOOTPROTO=none in the ifcfg file

Expected results:
The static configuration is applied in installer, ifcfg file is fine.

This is a regression from RHEL 7.3 (might be related to the new NM 1.8 in 7.4)

B) static (initramfs) -> dhcp (tui)

Steps to Reproduce:

1. Run text network installation with one NIC, activated with static configuration in initramfs (eg ip=10.34.102.233::10.34.102.254:255.255.255.0::ens3:none nameserver=10.34.39.2
2. In tui change the configuration to dhcp with applying it in installer environment (check 8) [x] Apply configuration in installer)
   - It is not possible to remove the nameserver, gateway and netmask options.

Actual results:
NIC gets dhcp address but also keeps static configuration (ifcfg file contains BOOTPROTO=dhcp and IPADDR, PREFIX, GATEWAY, DNS1 set)

Expected results:
NIC is recofigured with dhcp ip address, ifcfg file is fine (contains only BOOTPROTO=dhcp, no IPADDR, no PREFIX, no GATEWAY) 
Also it should be possible to clear nameserver, gateway and netmask settings in tui.

This is the same in RHEL 7.3.