Nerf survival time without food/water

[Clayell]

Fix #173
Nerf food survival time from 30 days to 3 days
Nerf water survival time from 3 days to 1 day

I decided to keep food higher than water, to emphasize the fact that food is more important. I would have put food at a week, but I really don't want people to send astronauts up for 6 days without any food at all. I feel like 3 days without food is the maximum where astronauts working 10 hour workdays would fail to continue working (and in space, that means you die).
1 day without water is pretty sensible as well, as a lot of body functions start failing after 1 day without water, and astronauts have a very strenuous work environment. (for anyone confused, remember that most of our water intake on earth is from water within food, but astronauts usually have dehydrated food)