It would be handy for .items support to be added to Tiles, just like we have .objects and .characters.
<tile>.items
An array of items currently occupying the tile, or null if there are none
This is extremely handy for diagnosing issues with add_item_to_tile(), as right now, i'm getting errors telling me a vacant tile already has a item on it, but it doesn't, and I cannot check for one/verify.
This will also allow for checking if a tile already has a item drop on it.
