Switch Nova to use oslo.concurrency

Let's switch to the newly released oslo library for the
processutils and lockutils. We use the config fixture(s) to
specify disable_process_locking and lock_path in the CONF
variable of oslo.concurrency library for correctly setting the
flags.

The previous attempt at updating nova to use oslo.concurrency
was reverted as it stopped running any tests. lockutils-wrapper
should have been used in ini/shell scripts
instead of lockutils.py module as the the module is
no longer runnable (__main__ has been removed).  In this
review we use lockutils-wrapper correctly. The test harness
has since been updated to bail out if 0 tests are run as
well for additional insurance.

Change-Id: I14c75ef2196fd08c9465d648e5cd53777bd9c7d1
Co-Authored-By: Nikola Dipanov <ndipanov@redhat.com>
Co-Authored-By: Corey Wright <corey.wright@rackspace.com>
Merge "Switch Nova to use oslo.concurrency"