Calculates and displays how much NP you need in the bank to reach max interest rate (with Ultimate Riches! Interest Rate), and if you have already reached max interest rate, how much NP you are able to withdraw without going below max interest rate.
A simple bank script for people aiming for the interest cap. It shows you how much NP you need in order to get to the interest cap if you haven't reached it yet ("Needed for Max Interest"), and if you've reached the interest cap it will instead show how much 'spare' NP you have in the bank that you can withdraw without going under the interest cap ("Max Interest Balance"). 
