Updated to 1.1

After a play-test today I made some small changes:

1. Changed the description for messy rooms in the room contents table.
2. Fixed an error in the traps table.
3. Fixed an error in the treasure table.
4. Gave the giant centipede more armour, because it's giant.
5. Re-arranged the treasure table slightly to better represent the power of items.
6. Added a rule for when a natural 1 is rolled on the hit dice. In version 1, only players got a benefit when they rolled a natural 8. It seems fair that enemies should get a benefit when they roll a natural 1.
7. Renamed the boss from "Skull Lord" to "Greater demon", because the first name felt a bit silly. And this way there's a reason for all those lesser demons to be skulking around.