move IMU integration out of drivers to sensors hub to handle accel/gyro sync

- IMU integration move from drivers (PX4Accelerometer/PX4Gyroscope) to sensors/vehicle_imu 
 - sensors: voted_sensors_update now consumes vehicle_imu
 - delete sensor_accel_integrated, sensor_gyro_integrated
 - merge sensor_accel_status/sensor_gyro_status into vehicle_imu_status
 - sensors status output minor improvements (ordering, whitespace, show selected sensor device id and instance)

src/modules/simulator/simulator.cpp

@@ -128,7 +128,7 @@ int simulator_main(int argc, char *argv[])
 
 		g_sim_task = px4_task_spawn_cmd("simulator",
 						SCHED_DEFAULT,
-						SCHED_PRIORITY_DEFAULT,
+						SCHED_PRIORITY_MAX,
 						1500,
 						Simulator::start,
 						argv);