OUYA: New official method to check for OUYA hw

Upgrading to ODK version 1.0.0 provides an official method to call for
determining whether the app is running on OUYA hardware.  I may have been
overly cautious using Class.forName here instead of calling it directly,
but I figured this would be the safest way to avoid potential problems on
other devices (and will allow the app to be built without having to
include the ODK jars)