cosmetics: cleanup installer output.

Silence irrelevant output from "dumpadm" and "zpool" test, because
it gets mixed in the middle of the lines from the installer output,
which results in unreadable mess.

Change-Id: I1ffe3e2cc7b34173eb70b721de5e8793b517dc7c
Signed-off-by: Piotr Sikora <piotr.sikora@frickle.com>
auto-config: add support for unattended installation.

This commit, when combined with ISO/USB image pre-populated with the
"/usbkey" directory containing basic configuration, adds the ability
to perform unattended installation. Just boot from the image and wait
for the configured system to come online.

Change-Id: Ie50912d0d00768c72cbf4d7a53165be1acd0d97c
Signed-off-by: Piotr Sikora <piotr.sikora@frickle.com>
auto-config: sources.list.sample is gone.

Change-Id: I81f2a7162676052c88faa11bc4c300f022cf0a3a
Signed-off-by: Piotr Sikora <piotr.sikora@frickle.com>