After every reset interval (whose exact length is determined on a mud
by mud basis, but averages around every 2 hours), reset() is called in
every object that currently exists. If LAZY_RESETS is defined in
options.h in the driver, reset() will only be called in objects when
they are touched (near players), so unused objects will not be loaded
from the swap file to reset. The reset() call is usually used to check
if any treasures and/or monsters in the room have been removed so they
can be replaced.