small changes

added masked/combine and zombie voices, removed isbox_playersilent, added isbox_voicetype (-1 = use the voice of your player model, 0 = silent, 1 = male, 2 = female, 3 = masked/combine, 4 = zombie), several fixes and improvements.

fixed players' views staying on their ragdolls when they respawn.

added the server cvar isbox_oldweapons which makes you spawn like you do in normal sandbox, with the physgun and other things