Make tox work in a fresh scenario

Severing the unit tests from the local config dependency
meant refactoring code that made pure unit testing
impossible. Introduced a conftest in this commit.

Change-Id: Id005b8b5b0704ccac33fa8768be1642941281f34
Issue-ID: DCAEGEN2-372
Signed-off-by: Michael Hwang <mhwang@research.att.com>
14 files changed