Changed riot zombie stumble trigger so we can stumble riot zombies at a long distance when !pa_awpriot is off

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Changed penetration damage trigger from weapon_fire event to bullet_impact event since the former event just killed entities we are aiming at regardless of whether those were hit or not

Added L4D1 riot zombie model used in some addon maps such as 'Cambalache - Buenos Aires' to penetration damage trigger

Added extra damage when charger who is charging is hit on the head so AWP can instant kill charger by headshot whether he is charging or not

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Added jockey instant kill ability

Added command for instant kill of riot zombies

Now AWPer can kill riot zombies by shooting their front or any parts of them