Various changes

[heinzema]

1. Added a ASCII statusbar for player stats and messages. (not handling messages that are longer than world.width -> overflow)
2. Implemented some kind of chance based AI for Enemy-Class. Bugs now move and attack - beware!
3. Damage made in an attack is now depending on the physical condition of the attacker and some chance (see comments).
4. Added a Player-Child-Class for further improvements such as learning skills etc. But it's still empty :-)