Render circular place=* as an unfilled area

Basically, give it area label placement, but line
behavior otherwise.

Test case: #id=w169604918&map=19.46/41.41402/-70.94773

css/map.css

@@ -359,6 +359,7 @@ path.fill.tag-amenity-parking {
     fill: #aaa;
 }
 
+path.fill.tag-place,
 path.fill.tag-boundary {
     fill: none;
 }