ZombieRounds
Fixes an issue with the Combat_Knife when obtaining Max Ammo. I suspect this bug will rear its head again in the future, so will code up a more specific solution.

Finally stops points from being acquired from mob kills outside of game and stops powerups being spawned outside of game.

Throwing_Knife is rewarded for completing each round.
Fixes a couple of bugs that were affecting vanilla events outside of the game mode.