Fix Debian compatibility

APT uses "amd64" instead of "x86_64" as the architecture label. Debian doesn't come with a `nobody` group, but uses `nogroup` instead. However, since the owner is `root`, I used the `root` group as well.

Gluster's repo is a little weird in that "wheezy" is hard-coded in the URL.
On Fri, Dec 19, 2014 at 4:28 PM, Lyle Mantooth <notifications@github.com>
wrote:
>
> Just release => 'wheezy'.
>
> Clearly I need to learn how to use Github better.
>


Oh no worries, I find the code review on GH is a bit awkward :)
And yes, that should be a variable, but it can come from within data/tree/