Added fists.

Added fists.
Fixed insane knockback on melee.
Ragdolls on zombies now knocked back by melee/stone deaths.
Fix a stupid moment.
SetWeaponHoldType -> SetHoldType
Merge branch 'master' of https://github.com/JetBoom/zombiesurvival

Conflicts:
	gamemodes/zombiesurvival/entities/weapons/weapon_zs_megamasher.lua
	gamemodes/zombiesurvival/entities/weapons/weapon_zs_zebulletstorm.lua