Added SNPCs Biomechanoids.

Added model Biomechanoid.

Added console command ssc_friendly_fire.

Fixed localization.

Added enemy killicons.

Flying and invisibles Gnaars now separated.
Zorgs are unlikely to shoot at their own Zorgs. (There is a bug that if the Zorgs have pinned down a player as a group, most of them will not shoot at him.)

Flying Gnaars now landing by death.

Added flying and invisible Gnaars.

And disabled friendly fire Reptiloid projectiles, except for themselves.

Disabled friendly fire for enemies who shoot weapons or throw projectiles.