Name: remove_data - remove stored data from a player

Syntax:
	mixed remove_data()

Description:
	The remove_data function removes data once stored with store_data from
	the player. Note that only the same object that stored the data can
	remove it again.

Return value:
	If there are any data, they are returned (after removing them),
	else 0.

Examples:
	this_player()->remove_data();

See also: build/player_data, player/store_data, player/query_data