Remove restart of libvirt-bin from notes.md

Restarting of libvirt-bin is now included in
scripts/install-dependencies so it's not necessary to
repeat it.
Reworking docs.
Adds qemu-img to list of required Red Hat packages

We need this to provide qemu-nbd.
Add qemu-utils for Debian/Ubuntu.

We need this for qemu-nbd.
Merge pull request #33 from pleia2/master

Remove restart of libvirt-bin from notes.md
Merge pull request #34 from dprince/install-deps-qemu-img

Adds qemu-img/qemu-utils to list of required packages.
More doc improvements.
Update architecture section.
Finish review of README.md.