First steps towards a d3 backend.
Introduce dataforms. Get something working.
A little more progress on figuring out data forms.
Some work on DataProperty.
Fix things. Flesh out the d3 backend a bit.
Misc property work.
Fix some data property things.
Guess text-extents when pango/cairo/fontconfig are unavailable.
Work without cairo, pango, etc.
d3 backend improvements
Less kludgy ways of setting clipping paths.
Fix a couple of things.
Clipping on the SVG and cairo backends.
D3 backend improvements.
Merge branch 'd3'