[Tilesathome] less inkscape calls in _unstable

[David Lynch]

> Maybe the way to go is to get rid of striped rendering alltogether and
> have users set their MaxTilesetComplexity appropriately if their
> Inkscape is eating too much memory.  As long as there are a couple of
> power-renderers that can handle those tiles we are probably fine.
>
> We can then have the client tell the server its MaxTilesetComplexity
> so the server won't hand out jobs the client will return anyway.
>
> This should ensure the best turn-around for rendering.

It seems like a good solution. I might recommend going a bit further
and giving MaxTilesetComplexity a value (somewhere around 8-10
million?) in the default configuration file and letting people opt in
to the biggest files, instead of the current unlimited value.

-- 
David J. Lynch
djlynch at gmail.com