Standardize exception syntax

[Stuart McLaren]

Some files have a mix of except X, y: and except X as y: syntax. Update to just use the newer 'except ... as' form.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/25377

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/25377
Committed: http://github.com/openstack/glance/commit/19b82a022cc58e702fe9061c3347cec471dc4da2
Submitter: Jenkins
Branch: master

commit 19b82a022cc58e702fe9061c3347cec471dc4da2
Author: Stuart McLaren <email address hidden>
Date: Tue Mar 26 12:14:55 2013 +0000

    Standardize on newer except syntax

    We currently have a mix of 'except X, y:' and 'except X as y:' syntax.
    Standardize on the newer 'except as' form.

    This patch was generated automatically using:

    find * -type f -name 'glance-*' ! -name '*\.conf' ! -name '*\.ini' -o \
     -name '*\.py' | xargs 2to3 -f except | patch -p0

    Addresses bug 1160331.

    Change-Id: Ica8d1303973af64d0406457267ee75f608e869d0