* Zombie dont have fall damage (damage by player 0 = server should always work) -> make it a CVAR, so for example zombies can't kill themselfs on same maps by going through lasers.

---- CRITICAL/IMPORTANT ----

* FIXED  --  fix spawn protection
  players gets invisible, but not protected against zombies.
  the array pProtect isn't used at all, just set to off and on.

* DONE  --  classes.inc:GetClassKnockback
  change class knockback to be a miltiplier of the default knockback (like the old ZR), not absolute values:
  knockback = default * class knockback


---- LOW PRIORITY ----

* zombie.inc:KnockBack / cvars.inc
  make cvar for shotgun/hegrenade knockback boost.

* make a admin command for reloading class data. useful when fine tuning knockback.

  and even better, if worth it:
  make admin commands for getting and setting each class knockback, like:
  SetClassKnockback(classindex, knockback)
  GetClassKnockback(classindex) - already there, just need to hook a admin command too

  cvars.inc:EnableHook
  another solution:
  zr_enable: disable: a "round draw" occour, then it's regular cs.
             enable: a new "round draw" occour and it's back.
  not sure if classes are reloaded. if LoadClassData can be executed twice there's no problem.