artf4170: Make CANTalon disable on destruction.

This both disables the CANTalon in the CANTalon class (which
should be redundant) and stops sending control signals in the
CanTalonSRX hal class.

Change-Id: I63d6a9d016c221e385d5d5a3679d854882ac6650

wpilibj/wpilibJavaDevices/src/main/java/edu/wpi/first/wpilibj/CANTalon.java

@@ -144,6 +144,7 @@ public class CANTalon implements MotorSafety, PIDOutput, PIDSource, PIDInterface
   }
 
   public void delete() {
+    disable();
     m_impl.delete();
   }