New "early guess" feature and new clue added to The Blackinton Curse

Test players for Murder Is Game Over: Murder Otaku reacted positively to the new "early guess" feature where you can attempt to guess the killer before the explanation scene happens. It is an optional feature, and the correct guess results in an additional scene with a trophy. Since the feature is easy to add, I added it for Murder Is Game Over: The Blackinton Curse. Also new is an additional clue to find. This just makes the story slightly improved. Hope players enjoy the game and the new content!