Yes, this should be zoom 12
Convert _links to use variables.
Move to a standard pattern for casing widths across road types.
Use variables for tertiary widths.
Add back in colours, tweaked slightly for new casing widths.
Standard casing widths for tertiary roads.
Remove the residential-thin, refs #52
Convert turning circles to use markers - allows automatic fill/casing colours.
Start making turning circles automatically adjust to road width, and have same casing widths as roads on that zoom.