If you had looked at the Stable Updates thread, then you would have seen that there was no need to remove anything. pacman-contrib is a spin-off from the pacman package, and thus the dependencies have changed. All you needed to do was… 
sudo pacman -Syu pacman-contrib
That would have updated your system and installed pacman-contrib all in one go.
While you’re at it, also tend to your .pacnew files, because there’s quite a few with this update. And you should merge them, not blindly copy them over, because then you won’t be able to log in anymore.