Level descriptions, using the AirStrike Interpreter.
In addition to these functions you can set variables by using
the NAME=VALUE syntax.



Existing
--------
bgelement name x y	  Create a foreground (colliding) element. name
			  refers to an image name.png in graphics/bg.
levelsize width height	  Sets the level size


Todo
----
sprite type x y		  Create a sprite of type at (x,y).
bgelement name x y	  Create a background (non-colliding) element.
playerspawn player_nr x y Sets the spawning point of player player_nr.
background r g b	  Sets the background color.

Future
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generator type sprite_type x y