Update to use sensible defaults for oslo.config

CONF should be passed the name of the application, which means
that /etc/stackalytics/stackalytics.conf will be what is looked for
in the absence of other options. This is great, since it's easy
to put a file in the place that defaults expect.

Change-Id: I11ff134da24931affadc58ad0989185ae6df7e92