Re-activate Allmendinger and Stenhouse

Signed-off-by: Greg Meiste <greg.meiste@gmail.com>
Future-proof Driver newInstance function by not returning null

If a player isn't running an up-to-date app, it may get an
unknown driver number as an answer. Instead of returning null
(which would cause a NPE), return a Driver object with the name
set to "Not Available". That's a bit more user friendly.

Signed-off-by: Greg Meiste <greg.meiste@gmail.com>