Only write data when changes occured

[lysogeny]

Currently the system always writes data from the item manager or account manager when the relevant application is exited.

This is unnecessary when no changes occured and can add considerable delay (and wear to the floppy) when all that was required was quickly checking balances.

[sur5r]

Please add more details to the description. The subject by itself is not specific enough to understand which part of the program you would like to see improved.