[Tagging] Update of article highway=mini_roundabout

[Martin Vonwald]

2012/5/24 Volker Schmidt <voschix at gmail.com>:
> the Irish road sign
> https://wiki.openstreetmap.org/wiki/File:Diamond_road_sign_roundabout.svg,
> which you show in your sample list of road signs for mini-roundabouts, is
> for a normal roundabout.
> You also show the correct Irish mini-roundabout sign
> https://wiki.openstreetmap.org/wiki/File:Diamond_road_sign_mini-roundabout.svg

Fixed! Thanks!