Rewrite population example to be easier to follow.
Fallback for projections that don't stream.
Improve locale parsing in Linux.
Rename for clarity.

d3_geo_cut is now d3_geo_clipAntimeridian.
d3_geo_circleClip is now d3_geo_clipCircle.
Minor optimization to d3.geo.circle.
Minor optimizations to d3_geo_resample.
Oops, add generated file.
Delete unused code.
Move rotation modulus to radian conversion code.
Optimize d3_geo_compose slightly.
Fix a bug with d3_geo_resample lineStart.
Optimise d3.geo.clip area calculation.

Only the area sign is needed to determine the polygon winding order, so
a fast approximation is sufficient.

U.S. counties benchmark: 84ms/op → 51ms/op.
Explain wondrous mathematics.
Increase threshold for ccw polygon detection.
Drop redundant variable.
Fix CCW polygon detection issue.

The south pole rotation could result in line segments that go through
the poles.  These are characterised by a 180° longitudinal difference.
These cases were not handled properly by the approximation algorithm,
but it now handles both north and south pole cases.
Restore tighter threshold for CCW polygons.
Coerce to number for d3.quantile.

This avoids string concatentation on fractional p-values.
Revert "Remove backwards-compatibility for d3.xhr."

This reverts commit c3635192d87c3c8ad573224283185c1b01c6b69b.
Use identity projection when null.