[Benchmarking] Some styling comparisons at different zoom levels

[Cédric Briançon]

Hi Andrea,

at every scales in the wiki, I can see that Geoserver has a white road, 
which one is in red for the others WMS output. This road is near the 
crossing of red roads, on the west side of a settlement, on the 1:31k 
map for example. You seem to have a specific rule for that kind of road 
to put it in white instead of red.
Is it a trunk road too?

Cheers,
Cédric