improper formatting in some NVP plugin exceptions

[dan wendlandt]

in some cases, the keyword arg passed to NVP plugin exceptions is incorrect, meaning the error message is not properly printed in logs. This is particular problematic when quantum is running from packages, which often default to non-verbose/non-debug, which does not show tracebacks. As a result, sometimes errors will look like:

2013-03-05 21:18:02.637 24350 CRITICAL quantum [-] An unexpected error occurred in the NVP Plugin:%(err_msg)s

where %(err_msg)s is supposed to be expanded to text explaining the error.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/23668

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/23668
Committed: http://github.com/openstack/quantum/commit/5584835f886302e434f9959f0f82f9694d09b5d3
Submitter: Jenkins
Branch: master

commit 5584835f886302e434f9959f0f82f9694d09b5d3
Author: Dan Wendlandt <email address hidden>
Date: Wed Mar 6 00:59:54 2013 -0800

    fix mis-matched kwargs for a few calls to NvpPluginException

    bug 1148839

    Change-Id: I7d08719c0ac9a7445f4863c91854e4dcd8c81be6