Name: set_level - set the level of a player

Syntax:
	set_level(int guild)

Description:
	The set_level sets the level of a player. 

	If the player is under 20 and is not your testplayer only a valid
	guild (located in /guild) may set the level of the player.

	If the player is over level 20 only an archwizard or domain lord
	(if the wizard is in the same domain) may set the level of a player.

	Note: If you try to set a player's level illegally, this will be
	logged!

Return value: none

Examples:
	this_player()->set_level(5);

See also: living/query_level