Fix a bug in d3.interpolateTransform.

I think d3.transform was inadvertently changed to d3_transform during
SMASH refactoring.  d3.transform is required here so that it can parse
transform specifications as strings.
Upgrade jsdom & uglify-js.
Add simple test for d3.interpolateTransform.
Fix a missing import.
Add d3.layout.voronoi.{links,triangles}.
Add PHONY targets.
Don't expose transient points.

Data-in and data-out. Although I could see it being useful to access the
computed coordinates, but I think in the common case, these will be implemented
as simple accessors.
Regenerate.
Merge remote-tracking branch 'remotes/mbostock-original/3.1.0' into all_scales_have_subticks

Conflicts:
	Makefile
	d3.js
	d3.min.js