Beginning on making interactable slots
Basic DragAndDrop skeleton for Frames and Items
Found a bug in this where swapping screens wouldn't stop the spawning
Drag and Drop picks up, but crashes on drop. Closer!
Drag and drop works with the right sprite, and doesn't crash on drop, but disappears when you drop it
Added elements to Groups for easy finding. Now Drop needs to be handled correctly!
Input multiplexers now set correctly  when moving between screens.
Moving a different direction:  instead of drag and drop, simpler controls for this alpha
Clearing unused statements
Clarity: make some constants actually constant
Starting to use the spacer
Formatting this class for readability, adding skeleton for next button
Moving Sort button to just in the inventory. Renders well enough for now.
Compress button is not needed yet! WORK ON PERTINENT THINGS FIRST!