Added heli_collectiveFactor array

Signed-off-by: Robert Lefebvre <robert.lefebvre@gmail.com>

ArduCopter/ArduCopter.pde

@@ -371,7 +371,7 @@ static uint32_t rc_override_fs_timer = 0;
 // Heli
 ////////////////////////////////////////////////////////////////////////////////
 #if FRAME_CONFIG ==	HELI_FRAME
-static float heli_rollFactor[3], heli_pitchFactor[3];	// only required for 3 swashplate servos
+static float heli_rollFactor[3], heli_pitchFactor[3], heli_collectiveFactor[3];	// only required for 3 swashplate servos
 static int16_t heli_servo_min[3], heli_servo_max[3];							// same here.  for yaw servo we use heli_servo4_min/max parameter directly
 static int32_t heli_servo_out[4];												// used for servo averaging for analog servos
 static int16_t heli_servo_out_count;											// use for servo averaging