Bug hunting

I've found and fixed three bugs that were present in release 1.5. The first was in the flooding routine and caused a rather silly looking 'wall-of-water' effect. It occurred very rarely, which is why I didn't notice it before. The second was that the infinite-wrapping function didn't work properly due to an oversight in the inflation routine. The third was in the shadow-casting routine, which gave erroneous small shadows depending on the lighting direction. The fixes will be included in release 2, which I'm guessing is about a week away.