[Geojson] Draft version 6 in restructured text and HTML

[Sean Gillies]

The only changes I made were 1) a little restructuring to keep the CRS
section from going 6 levels deep, 2) change "location" to "geometry" in
the blog example.

http://zcologia.com/sgillies/hg/geojson-draft/raw-file/tip/geojson-draft-6.txt
http://zcologia.com/sgillies/hg/geojson-draft/raw-file/tip/geojson-draft-6.html

Does the example using coordinate_order need to go? I left an admonition
in there to mark it.

http://zcologia.com/sgillies/hg/geojson-draft/raw-file/tip/geojson-draft-6.html#id44

To do: make use of quotes and italics consistent throughout the
document. Perhaps add internal links.

Sean