Prevent fire burning on water tiles

[thesixthroc]

If you throw fire from a flamethrower, it will maintain a fire on tiles like water-shallow, which seem wrong.

[robot256]

Seems perfectly normal to me. Oil floats on water, and burning oil still burns while it floats (if the water is smooth). Maybe it should go out a little quicker, but that's a tiny detail maybe not worth coding.

[thesixthroc]

That's a good point. I'd make it go out faster: The details matter more in scenarios with lots of water, like Pirate Ship.