msg: vehicle_local_position_setpoint: add yawspeed as a state you can control

msg/vehicle_local_position_setpoint.msg

@@ -5,6 +5,7 @@ float32 x		# in meters NED
 float32 y		# in meters NED
 float32 z		# in meters NED
 float32 yaw		# in radians NED -PI..+PI
+float32 yawspeed# in radians/sec
 float32 vx		# in meters/sec
 float32 vy		# in meters/sec
 float32 vz		# in meters/sec