Added first proto-quest to janthus (http://www.janthus.com) -- clear the ratcave, kill the king!

Added the first quest-type point to the game: descend into the Rat Cave (entrance at 122,62 inside the small cave in the starter castle), and clear out all the rats (50 of them). If you survive (and you should, the rats are easy) -- the Rat King will appear in the cave to challenge you. Kill him (very tough) and his rat minions will return).

This represents several milestones in the game:
* introduction of submaps/subworlds -- no longer is the game restricted to one gigantic overworld, you can now go to different self container worlds, possibly hosted somewhere else
* introduction of the quest element, as opposed to random pillaging and exploration

I've also very much solidified the networking aspect of the game, so if you have a reasonable connection to the internet, the game should play fine.

Let me know what you guys think (and if you can kill the Rat King, whether or not he's too hard, etc.).