Add an ST_Simplify(TopoGeometry) override

[strk]

Such function would take advantage of the topological definition of the geometry and while still returning a simple geometry it would still perform the simplification retaining primitive nodes.

[strk]

r11158 implements this. Lacks documentation, but I'm not sure how to best encode that. I'd rather re-use the existing "ST_Simplify" section, but @robe mentioned that's a no-no due to automatic tests generated in there and possibly breaking when you don't have topology installed. Needs another ticket ?

[strk]

r11159 documents it (the way robe wanted it)

[robe]

hmm -- shouldn't the short description be:

Returns a "simplified" geometry version of the given TopoGeometry using the Douglas-Peucker algorithm.

[strk]

r11160

See also  http://strk.keybit.net/blog/2013/03/08/on-the-fly-simplification-of-topologically-defined-geometries/