- Added support for THRU flags on bullets and rails.

- ALLOWTHRUFLAGS must be used on the puffs, added for the sake of compatibility with older mods. This applies to the following:
-- Bullets: THRUACTORS, THRUSPECIES
-- Rails: Same as bullets, but includes THRUGHOST.

src/actor.h

@@ -380,6 +380,7 @@ enum ActorFlag7
 	MF7_FORCEDECAL		= 0x00080000,	// [ZK] Forces puff's decal to override the weapon's.
 	MF7_LAXTELEFRAGDMG	= 0x00100000,	// [MC] Telefrag damage can be reduced.
 	MF7_ICESHATTER		= 0x00200000,	// [MC] Shatters ice corpses regardless of damagetype.
+	MF7_ALLOWTHRUFLAGS	= 0x00400000,	// [MC] Allow THRUACTORS and the likes on puffs to prevent mod breakage.
 };
 
 // --- mobj.renderflags ---