Update CHANGELOG

Author: mbostock

CHANGELOG.md

@@ -20,7 +20,7 @@ The new *clip* mark option enables clipping to the plot frame. For example, this
 d3.ticks(0, max, bands).map(t => Plot.areaY(traffic, {x: "date", y: d => d.value - t, fill: t, clip: true}))
 ```
 
-Plot can now generate helpful warnings for common mistakes. Warnings are indicated ⚠️ in the top-right corner of the plot; open your browser’s developer console to read the warnings. For example, if you forget to parse strings to dates resulting in an *ordinal* scale rather than the desired *utc* scale, Plot will advise on how to fix the scale definition.
+Plot can now generate helpful warnings for common mistakes. Warnings ⚠️ are indicated in the top-right corner of the plot; open your browser’s developer console to read the warnings. For example, if you use data with date strings resulting in an *ordinal* scale rather than the desired *utc* scale, Plot will advise you to parse strings to dates.
 
 <img src="./img/warning.png" width="640" alt="a horizon chart of unemployment rates by metro area; increases are shown in red, and decreases in blue">