Changed all of the § signs to bukkit's ChatColor method!

After 2 hours of work, I've finally managed to replace every single § sign (except for commented code and the MoTD) to use bukkit's ChatColor method.

I also made 2 little changes :

1. Once a player joins, his health and hunger bar is refilled. Both are refilled again once the game starts. (I will later change it so that hunger/health never drains unless you're in joined and in game.

2. I had a bit of fun and edited the Demo kit and replaced the 8 redstone torches with a flint and steel to facilitate tnt ignition and to give the kit a more "Demolition" feel :P