Change `Inventory` commands `remove` and `drop` to use file name instead of object name

[CalebKendra]

Inventory might be better if drop and remove use the file name to show the object instead of the object name. such as Tomato.py instead of Tomato. Need to update CONTRIBUTING and readme in yard if this is done

[dluman]

I assigned this to @CalebKendra -- good way to get into what inventory does!