Name: query_vis - get the visibility status from a player

Syntax:
	int query_vis()

Description:
	The query_vis call gets the visibility status of a player.
	This function currently doesn't make much sense, since invisibility
	is defined by not returning a description from short(). However one
	could think that the short() function in wizard.c one day is made
	to return a description only for wizards, when a wizard is invisible.
	So you need to use this function to be sure. Heh.

Return value:
	If the player is visible, 1 is returned, else 0.

Examples:
	int vis;
	vis=this_player()->query_vis();

See also: w/vis, w/invis