Putting gold into a hero-owned container on a shop's floot gave credit
for the amount of the gold but also set the gold object no_charge, so
it could be taken out without taking away the credit. Then put back
in and taken out as many times as the player liked, doubling the gold
each time until the shopkeeper was out of cash.
I think the proper fix would be to avoid giving credit instead of not
marking the gold no_charge, but that would require multiple additional
changes so I took the easy way out.
Most of the changes to pickup.c are reformatting that it escaped prior
to release. The changes to shk.c are cosmetic and not part of the fix.
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