[PATCH 2/2] docs: Update installation guide for Ubuntu 16.04

[Stephen Finucane]

On Tue, 2017-05-02 at 00:56 +0100, Stephen Finucane wrote:
> Use the latest LTS version of Ubuntu. This is mostly a simplification
> of
> the guide, which reverts back to single-node configuration and
> increases
> the emphasis on installing system packages rather than using 'pip'.
> There are also a series of corrections, mostly around using the
> Python 3
> variants of packages.
> 
> Signed-off-by: Stephen Finucane <stephen at that.guru>

I ran through this last night on a Debian 9 (Stretch) RC3 VM. Worked
exactly as expected, a few typos aside. Made those corrections and
applied both patches.

Stephen