Name: query_testplayer - check, if a player is a testplayer

Syntax:
	string query_testplayer()

Description:
	The query_testplayer call checks if a player is a testplayer of another
	wizard.

Return value:
	If the player is a testplayer of a wizard, this function returns the
	name of the wizard, else 0.

Examples:
	string testplayer;
	testplayer=this_player()->query_testplayer();

See also: build/testplayer