Lfun:	query_ac - return the amount of armour class of a living

Synopsis:
	int query_ac()

Description:
	The query_ac call returns the amount of armour class of a living. The
	armour class is calculated from all the armours a living is wearing.

Return value:
	A positive integer indicating the armour class.
	If no armour is worn, 0 is returned.

Examples:
	int ac;
	ac=this_player()->query_ac();

See also: monster/query_def_ac, monster/set_ac, living/query_wc