Renamed venturi_usa to venturi; International is the base device
* Fixed README and setup-makefiles.sh
* No functional changes.

Change-Id: I2c97fc2666f27143f9cee44ad27a1f4f6fba7150
Use more versatile extract-files.sh

Change-Id: Ieb9b51707a3a4621d501c9fe8d9f526e94302dc1