Better commodity trash functions

[Deantwo]

1. Trash Max Button - When trashing commodities in a city, add a "max" button (location in the red area bellow perhaps) so the highest value can be automatically entered into the quantity field instead of typing the number out each time.

I still don't know why we need to type an amount at all. When would you ever need to trash a small amount of a stack? When I want to trash something, it is normally every last item in the selected stack.

5000 Q90 Computers? You need to make room for the Q255 Computers you can now make, so lets trash 100 Computers, right? Wrong, I always want all of the bad Computers gone forever, right now.