Migrate to argparse. optparse is deprecated.
Migrate to argparse. optparse is deprecated.

Change-Id: Id82cfbefae4613e16eb2a602267fdacb8a1afa56

meelapshah/git-review,meelapshah/git-review,ka2m/git-review,openstack-infra/git-review,entropia1/git-review,jeeloo/git-review