Exception not being raised properly

[Brian Metzler]

Fixing autocomplete typo on raise exception.

poppy ERROR [-] Could not load 'mailgun': exceptions must be old-style classes or derived from BaseException, not bool
poppy ERROR [-] exceptions must be old-style classes or derived from BaseException, not bool
poppy ERROR Traceback (most recent call last):
poppy ERROR File "/opt/poppy/env/local/lib/python2.7/site-packages/stevedore/extension.py", line 163, in _load_plugins
poppy ERROR verify_requirements,
poppy ERROR File "/opt/poppy/env/local/lib/python2.7/site-packages/stevedore/named.py", line 123, in _load_one_plugin
poppy ERROR verify_requirements,
poppy ERROR File "/opt/poppy/env/local/lib/python2.7/site-packages/stevedore/extension.py", line 188, in _load_one_plugin
poppy ERROR obj = plugin(*invoke_args, **invoke_kwds)
poppy ERROR File "/opt/poppy/poppy/notification/mailgun/driver.py", line 73, in __init__
poppy ERROR % self.from_address)
poppy ERROR TypeError: exceptions must be old-style classes or derived from BaseException, not bool

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/312983

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/312983
Committed: https://git.openstack.org/cgit/openstack/poppy/commit/?id=190fe442bc8e7af7bc7d347a391c425823ccb382
Submitter: Jenkins
Branch: master

commit 190fe442bc8e7af7bc7d347a391c425823ccb382
Author: Brian Metzler <email address hidden>
Date: Thu May 5 10:13:57 2016 -0400

    Changed the 'raise validate_email_address' to 'raise ValueError'
    Closes-Bug:1578643
    Change-Id: I15c937cf21829042e0ee725f45bb74b8084d9d41