Add autoshoot

If this cvar is enabled (1), and the aimbot is enabled (fov>0), it will
stop attacking if there is no visible target.

src/include/cvars.h

@@ -33,6 +33,7 @@
 DECL_CVAR_EXTERN(bhop);
 DECL_CVAR_EXTERN(autostrafe);
 DECL_CVAR_EXTERN(aimbot);
+DECL_CVAR_EXTERN(autoshoot);
 DECL_CVAR_EXTERN(esp);
 DECL_CVAR_EXTERN(chams);
 DECL_CVAR_EXTERN(crosshair);