moving items from one item slot to another in main UI

[Tsunder]

causes the original location of the item to be unusuable (double clicking should bring up edit item window but instead does seemingly nothing.) additionally, moving an item (drag n drop) to another slot overwrites the target slot, perhaps should be swapping location?

[wizzomafizzo]

this is the same as #25 but i think i'll swap to this one since you've described the issue a lot better

i'm still figuring out how drag n drop works exactly in qt but i want to fix this so bad