Suggest using a foldable tree view for the SDF specification

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Hi all,

I'm not sure if this is the place to post, but regarding the SDF documentation (http://gazebosim.org/sdf.html), could I suggested that there be a foldable tree view or at least lines that indicate which level of indentation the tags are in? Something like this:

(Image taken from Google) It is pretty painful to figure out which tag goes under the other once scrolling down the left hand menu pain.