[Python-buildbots] Buildbot 9 + Postgres backend

[Zachary Ware]

On Fri, Oct 6, 2017 at 3:36 PM, Craig Rodrigues <rodrigc at crodrigues.org> wrote:
> I'd like to suggest that when we upgrade the buildbot master,
> we use a Postgres backend instead of sqlite:
>
> http://docs.buildbot.net/latest/manual/cfg-global.html#postgres

Since it's such a simple change, we can just factor `db_uri` out to
`local.py`, defaulting to sqlite, and we can switch to postgres at our
leisure later.  I'm not concerned about resetting the database to do
so.

-- 
Zach