Add Cyborg's multi suggestions

Author: MjnMixael

code/object/collideshipweapon.cpp

@@ -865,10 +865,9 @@ int collide_prop_weapon(obj_pair* pair)
 	Assert(weapon_obj->type == OBJ_WEAPON);
 
 	// Cyborg17 - no ship-ship collisions when doing multiplayer rollback
-	//Asteroth - should this be kept?
-	/*if ((Game_mode & GM_MULTIPLAYER) && multi_ship_record_get_rollback_wep_mode() && (weapon_obj->parent_sig == OBJ_INDEX(ship))) {
+	if ((Game_mode & GM_MULTIPLAYER) && multi_ship_record_get_rollback_wep_mode() && (weapon_obj->parent_sig == OBJ_INDEX(prop))) {
 		return 0;
-	}*/
+	}
 
 	if (reject_due_collision_groups(prop, weapon_obj))
 		return 0;

code/ship/shiphit.cpp

@@ -1172,7 +1172,9 @@ static void shiphit_record_player_killer(const object *killer_objp, player *p)
 		break;
 
 	case OBJ_PROP:
-		// handle this
+		strcpy_s(p->killer_parent_name, "");
+		p->killer_species = -1;
+		p->killer_parent_name[0] = '\0';
 		break;
 
 	case OBJ_NONE:
@@ -1581,6 +1583,7 @@ static void player_died_start(const object *killer_objp)
 		case OBJ_SHIP:
 		case OBJ_DEBRIS:
 		case OBJ_ASTEROID:
+		case OBJ_PROP:
 		case OBJ_NONE:	//	Something that just got deleted due to also dying -- it happened to me! --MK.		
 			other_objp = killer_objp;
 			break;
@@ -1594,9 +1597,6 @@ static void player_died_start(const object *killer_objp)
 				other_objp = &Objects[beam_obj_parent];
 			}
 			break;
-		case OBJ_PROP:
-			//hmmmmmm
-			break;
 
 		default:
 			UNREACHABLE("Unhandled object type %d in player_died_start()", killer_objp->type);		//	Killed by an object of a peculiar type.  What is it?