Vomiting

Make vomiting thirst/hunger scale lower as you get more hungry/thirsty. Dying due to starvation from vomiting should no longer be possible, but it is still possible to die due to dehydration from vomiting (though it takes a much longer time).

Also removed references to time in the starving/dehydrated messages (as getting the message "you haven't eaten for two days" when you vomit up your guts is weird) and slightly reduced message frequency.