Add short options to tempest
Add short options to tempest

Add short options for '--smoke' and '--serial' to the tempest command
line arguments for compatibility with `run_tempest.sh`.

Change-Id: I2736637680f509e54c8c76df4a31490049dd4d4e

masayukig/tempest,openstack/tempest,cisco-openstack/tempest,openstack/tempest,Juniper/tempest,vedujoshi/tempest,cisco-openstack/tempest,masayukig/tempest,vedujoshi/tempest,Juniper/tempest