isRunning() incorrect in some cases

[QuirkyCort]

isRunning() returns false only if speed is not zero and distanceToGo is not 0, but when using runSpeedToPosition(), the speed is not set to zero even when the target position is reached. This means that when using runSpeedToPosition(), isRunning() always return true even when the move is completed. The following change should fix this...

boolean AccelStepper::runSpeedToPosition()
{
    if (_targetPos == _currentPos)
    {
        _speed = 0.0;
        return false;
    }
    if (_targetPos >_currentPos)
        _direction = DIRECTION_CW;
    else
        _direction = DIRECTION_CCW;
    return runSpeed();
}

Also, when using runSpeed(), the target position is not set, so isRunning() may return true even if the speed is set to zero. Changing isRunning() to use || instead of && should fix this (...as well as the previous problem), but I haven't looked into the code enough to determine if it'll cause other issues.

bool AccelStepper::isRunning()
{
    return !(_speed == 0.0 || _targetPos == _currentPos);
}