Update CHANGELOG

Author: mbostock

CHANGELOG.md

@@ -82,7 +82,7 @@ The *color* scale now defaults to an *identity* scale if all associated defined
 Plot.barY(alphabet, {x: "letter", y: "frequency", fill: d => /[AEIOU]/.test(d.letter) ? "red" : "black"})
 ```
 
-The *color* scale now has a special default range for boolean data, encoding false as light gray and true as dark gray. (You can opt-out of this by setting the scale type to *categorical* or by specifying a *scheme* or *range*.)
+The *color* scale now has a special default range for boolean data, encoding false as light gray and true as dark gray. (You can opt-out of this by setting the scale type to *categorical* or by specifying an explicit *range*.)
 
 [<img src="./img/boolean-color.png" width="640" alt="a chart with grey and black bars">](https://observablehq.com/@observablehq/plot-bar)