- Have `Servo::attach` explicitly return -1 if it fails
- Check for -1 in `Servo::move` because `servoIndex` might be 0
- Make `attach` / `detach` calls conditional on `SERVO_LEVELING`
- Move `SERVO_LEVELING` define to `Conditionals.h`
move(pin, angel) - Sequence of attach(pin), write(angel),
if DEACTIVATE_SERVOS_AFTER_MOVE is defined waits SERVO_DEACTIVATION_DELAY, than detaches.
As we have jitter on the servos during moves of the steppers, and detaching them improves this behaviour,
the usual sequence to handle a servo movement is:
attach(pin)
write(angel)
delay(until the servo finished the move)
detache()
Here a function to handle the complete sequence.
