This should make it easy to run any Python version test, e.g. Python 3.6,
without any further change.
Change-Id: I91a47b736371549e50b7c7fd60e46e0f87c357ae
This makes sure that the test fails if not URL is set. This allows make sure we
test the non-coordination tests (e.g. partitioner) with all base drives (zake,
ipc, file) by using the TOOZ_TEST_URL to run the tests.
Change-Id: Id500636d166e5ebcc54fda16ef128f91f32170d6