Added many new features in the Munition class:
- there are now 3 modes:
a) every weapon has it's own magazine
b) all weapons use the same magazin
c) no magazines, just a big munition pool
- the Munition class handles the reloading of the magazine
Split the Weapon class into Weapon and WeaponMode. WeaponMode creates the fire of the Weapon. A weapon can own several WeaponModes (for example primary and secondary fire). But it's also possible to have a weapon with several muzzles which all fire at the same time (there's a WeaponMode for each muzzle).
Renamed LaserGun to LaserFire and Fusion to FusionFire. They inherit now from WeaponMode.
Changed the code in the Weapon class to use the new Munition functionality.
Added ReplenishingMunition, a subclass of Munition that replenishes itself (used for LaserGunMunition).
Added a reload command to reload magazines.
