1 - bring CSS lexer to the CSS2.1 spec (http://www.w3.org/TR/CSS2/syndata.html)
2 - CSS override rules are broken. For example, text-offset-y and text-offset
3 should override each other, but currently they are mixed upon rendering.
5 - Fixing of label positions should include some margin
8 - Add icon-anchor-* properties like text-anchor-*
9 (for now, we have only icon-offset-*)
11 - do something with (major-)z-index-fixup ... better typesetting of bridges?
12 - way[layer="2"] requires quotes