Implemented "Shift + Left Click" for ItemDiviner to get previous Ritual

Ever got tired of cycling through all the rituals by Shift + Right Clicking the item diviner to just miss the one you wanted and then have to do it all again?

This change allows to "Shift + Left Click" to cycle through the rituals in the opposite direction. The only downside is that you can't quite spam the "Shift + Left Click" as you can for the Right Click, you have to do it one at a time. But I think it's still really useful and others might agree.