v0.3.2b: fixed a bug where the caves boss floor sign would sometimes appear under a trap

src/com/shatteredpixel/shatteredpixeldungeon/levels/CavesBossLevel.java

@@ -189,7 +189,7 @@ public class CavesBossLevel extends Level {
 		int sign;
 		do {
 			sign = Random.Int( ROOM_LEFT, ROOM_RIGHT ) + Random.Int( ROOM_TOP, ROOM_BOTTOM ) * WIDTH;
-		} while (sign == entrance);
+		} while (sign == entrance || map[sign] == Terrain.INACTIVE_TRAP);
 		map[sign] = Terrain.SIGN;
 	}