Add missing pre.d directory to let user know they can use such scripts
Preserve console directievs from kernelargs into installed system
Retry umount during image2disk, if processes have the filesystem busy.
Fix DNS behavior during post phase of installtodisk
Invoke confignet properly during firstboot to set up additional interfaces.
Have sshd run during the install from '/sysroot', for convenience
Fix some cosmetic error output for setupssh
With significant firstboot output, there was a tendency
for tail to be killed before it relayed all the content.
Change to run the firstboot in a subshell in the background,
and have tail explicitly run until that subshell naturally
exits and then tail will cleanly exit
