[Tilesathome] New border rendering based on admin_level

[Patrick Kilian]

Hi all,

a patch introducing new border rendering based on admin_level is
available at:
http://trac.openstreetmap.org/attachment/ticket/1332/border-v1.patch

A osm file for rendering to get a feel for the style is available at:
http://trac.openstreetmap.org/attachment/ticket/1332/border.osm
This file is for rendering only and not fit to be uploaded!

The patch falls back to border_type if no explicit admin_level is given.
It assumes that nation / country are equivalent to admin_level=2, region
 / state are equivalent to admin_level=4, county / district are
equivalent to admin_level=6, municipality / city are equivalent to
admin_level=8 and suburb is equivalent to admin_level=10. This is
consistent with the wiki and the majority of the ways tagged with both
border_type and admin_level.

Please give feedback, especially for the case of z12 and low zoom.

Happy New Year,
Patrick "Petschge" Kilian