[CREATE] OpenRaster spec updated

[Martin Renold]

hi,

FYI, I have now updated the layer stack specification.
http://create.freedesktop.org/wiki/OpenRaster/Layers_Stack_Specification

Removed x, y from the image.
  As discussed. Implementation status: [1]

Removed width and height from the layers.
  As discussed. Implementation status: [1]
	
Renamed "width" and "height" attributes to "w" and "h".
  This is how it already was in the example.
  Implementation status: [1]

Made image "w" and "h" attributes mandatory.
  As proposed in a previous mail. I think the only argument against it
  could be an OpenRaster file that defines a unbounded image. This
  special case can have an extra image attribute, and even then it
  makes sense to define a default canvas size to display it. [1]

[1] Krita, DrawPile and MyPaint already seem to save it correctly.

bye,
Martin