Sound updates

Some sound files are being brought up-to-date.  Some of the configuration items, like and were wrong.  Also, I've added a new channel to the ADC which models a 3-gear squat switch with a two second delay.  This should solve once and for all the problems I've had getting the "tire squeal" sound to play at the right time.  

Edit:  The sound problem is solved on runways, but not on the carrier.  The problem is that airplanes using the JSBSim FDM no longer initialize properly on the carrier.