clean up sample index

- ensure foreign key columns are indexed (InnoDB adds these
indices implicitly so make sure index doesn't already exist)

Change-Id: Ia40c226ffea54cb07980864f0df1cb186dafd352
Fixed various import issues exposed by unittest

Tried running the unit test stand-alone(e.g. using testtools.run), and
it exposed various 'import' issues about the oslo.config options and the
modules, in both the test cases themselves and the ceilometer module.
This patch fixed those import issues.

Change-Id: I68f30d335ee8d0d63c451116274632287a9ec77f
Closes-Bug: #1328796
Merge "clean up sample index"
Merge "Fixed various import issues exposed by unittest"