Remove redundant Sizzle.uniqueSort call
Shorten selectAll to just `Sizzle`
100% to 125% faster #rgb/#rrggbb string parsing across all platforms. Tests pass. http://jsperf.com/rgb-str-vs-regex
Better ticks for subsecond domains.

Rather than starting the ticks on the minimum domain value, round up based on
the step size. Fixes #1757.
Merge branch 'fix-conic-conformal' into 3.4.4