As pointed out by Vish, there are duplicates of:
OverridesTestCase::test_default_override
OverridesTestCase::test_override
SadPathTestCase::test_conf_file_not_found
Also, rename the ConfigFileOptsTestCase so it is obvious they
don't clash with the tests by the same name in CliOptsTestCase.
Change-Id: I5cda3c4796b98eaf0e99589579d0b3bceaf9cd8b