Added new integrity print.
Now attack is added to hitDamage.
Solved the killing in the dark bug.
Encapsulated food.

Also implemented eating experience.

Additionally, this commit removes some unused methods from Hero.java.
Started a world generator.
Created a clock component and made a clock.

Also many small fixes here and there.

Noticeably, Item got a Creature field for its owner.

As this commit is reasonably big, it may introduced a bug or two.
Adds Apache Commons Lang.