Avast should detect Tuto4PC. The fact is, it is not.
All the important informations about Tuto4PC are in the french topic indicated by Malekal_morte : http://forum.avast.com/index.php?topic=81827.0

Quick translation :

Would it be possible to protect Avast users from Tuto4PC ? Take a look at these programs. If you think they are malware, adware or PUP, add detection for Tuto4PC. Given the feedback from users on various websites, I think they would agree to add detection for such programs.