defs.h:
	add F_WHATEVER

io.c:
	update makedesc_ob() for when an object confers this property

	update showlfstats() to show temporarily gaining the property
	update makedesc_race() to show the property as a racial characteristic
		(strength/bonus)

	update announceflaggain() to describe adding it
	update announceflagloss() to describe losing it


then make it do something!