Raising warnings from an exception module can result in a rather
confusing message:
Running command: '/usr/bin/nova-scheduler '
/.../sqlalchemy/enginefacade.py:332: NotSupportedWarning: Configuration option(s) ['use_tpool'] not supported
exception.NotSupportedWarning
For someone not used to Python's 'warning' infrastructure, this can look
worse than it is, as seen at [1].
While this particular warning was resolved in change I4a5f8958c3e, it's
possible that a similar warning could be raised for other options. Best
to move this out of the 'exception' module and into something more
sensible.
[1] https://bugzilla.redhat.com/show_bug.cgi?id=1639423
Change-Id: I8e0480fb11123067a111ed6aeda6b47614615645
Signed-off-by: Stephen Finucane <stephenfin@redhat.com>