[BUG][0.8] Limitless water from Kitchen Unit

I have a RV kitchen unit installed onto a bus that seems to let me drink from it indefinitely even though the water tanks are empty.

shhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
Just smash open that puppy, and let the world flood with infinite water

Another problem with the kitchen unit is if you 'e’xamine it and say Yes fill a container, but do not choose a container, it empties every water tank on the vehicle to 0%.

Yep, I can attest to this. Seems to happen when you attempt to use the kitchen unit to fill up an object that’s already full; for some reason, this empties the water tank to a very small negative number, causing some sort of underflow glitch that henceforth gives you infinite water to drink.

Similarly, one can fill the kitchen unit with a very small amount of water, the remove it by filling that water into a container, and you’ll still be allowed one drink from the kitchen unit despite its tank being empty.

Fixed in https://github.com/CleverRaven/Cataclysm-DDA/pull/3264 .

Basically, it was taking all the water out, and didn’t put it back in if you cancelled.