INCOMPATIBLE: In Pango mode, the direction of rise and lower
has been reversed and is no longer proportional to the font size.
In convenience mode you can use percentages and points..
INCOMPATIBLE: Extent boxes are now relative to top-left. This
is Pango compatible and makes the box fit when drawn at the
same coordinates the layout was rendered.
(Internal) Add extents method for CID fonts.
More Pango compatibility.
Add font properties direction and language.
Add 'pt' postfix for point sizes in markup.