Added loop within conditional

If character name is entered a for loop begins. The for loop is indexed
at 2, and decrement by 1 until it reaches 0. This gives the user two
turns to attack and slay the boss. The boss health is checked after the
loop breaks. If the boss is not slain within the two turns, the user
has failed and a message is displayed. If the boss is slain, the user
has succeeded and a message is displayed.