rank (d3#228)

* rank

* only implement “low” ties strategy (d3#236)

* only implement “low” ties strategy
* only test “low” ties strategy
* only allow iterables
* adopt Float64Array.of
* documentation: remove ties; observablehq/@d3/rank
Co-authored-by: Philippe Rivière <[email protected]>

* not an iterator

* main

* tweak tests

Co-authored-by: Mike Bostock <[email protected]>

Author: Fil