ISSUE-2293 (image-intrinsic): Should be possible to determine intrinsic size of an image [SVG Core 2.0]

ISSUE-2293 (image-intrinsic): Should be possible to determine intrinsic size of an image [SVG Core 2.0]

http://www.w3.org/Graphics/SVG/WG/track/issues/2293

Raised by: Cameron McCormack
On product: SVG Core 2.0

There should be attributes on an <image> the expose the intrinsic size of the image it references, possibly also its resolution.  This should be straightforward in most cases, though I'm not sure what values would be returned for, say, an SVG image that has percentage width/height.  Maybe aspect ratio should be exposed separately from width and height.