cleanUp() removing all test resources as an admin

Add a parameter in tempest.conf "full_clean_stack" to
allow/prevent the use of cleanup() method at the end
of a stress test run.

This is mandatory to use stress tests in a multi-user
environment since the actual cleanup() is designed to
remove every object of every tenant (and thus will
impact other users on the same openstack)

Change-Id: I42dc9592617aeeca9660f670940ecbf50b6108ab
Closes-Bug: #1273254
3 files changed