pep8: vdsm cleanups for pep-1.5.x

vdsm/*.py is now pep8 1.5.x clean.

Change-Id: I43aec2d5c9d32f816813f575876cd458cc53b886
Signed-off-by: Francesco Romani <fromani@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/26382
Reviewed-by: Antoni Segura Puimedon <asegurap@redhat.com>
Reviewed-by: Dan Kenigsberg <danken@redhat.com>
Reviewed-by: Federico Simoncelli <fsimonce@redhat.com>