[Geojson] GeometryCollection not treated as a Geometry type

[Christopher Schmidt]

Currently, GeometryCollection is not treated as a geometry type. This is
essentially an oversight -- up until now, the people primarily working
on the spec didnt' really use GeometryCollection, to the best of my
knowledge.

This oversight bit me in the ass earlier today when I added the Union
operation to:

  http://crschmidt.net/mapping/wpserverdemo/

Draw a Polygon, draw a line, click union, and you'll see that although
OGR dutifully returns a JSON-ified geometry collection, OpenLayers can't
handle it.

So, I'd like to propose we modify the specification so that
GeometryCollection really is treated as a geometry -- since that's what
the rest of the tools out there seem to do.

Tim is working on patching OpenLayers, I'm going to work on changing the
spec.

Any disagreements can obviously result in us rolling the specification
changes back.

Regards,
-- 
Christopher Schmidt
MetaCarta