Rule changes, and created game simulator

Quite a lot of big changes:

* Massively changed game rules
    * Ships only move one square, but can move diagonally
    * Ships can move with more than 3 loot, but must not have more than 3 loot when their turn ends
    * Added Merchant Ship, which acts similar to Towns
    * Added four more dragons (Hydra, Kraken, Cthulhu, Flying Dutchman)
    * Rebalanced card ratios
    * Amulets are discovered at Treasure Islands, instead of while exploring
    * Amulets can kill all dragon types when on their elemental location
* Created hbdsim.py
    * It simulates the game following the rules
    * Map is shown in real time of ships and locations
    * Very basic incomplete player AI explores the map