DOC: Add whatsnew note

Licht-T · Licht-T · commit 87d082e8d1b7 · 2017-11-26T10:13:47.000+09:00
diff --git a/doc/source/whatsnew/v0.21.1.txt b/doc/source/whatsnew/v0.21.1.txt
@@ -93,7 +93,7 @@ I/O
 Plotting
 ^^^^^^^^
 
--
+- Bug in ``DataFrame.plot()`` and ``Series.plot()`` with :class:`DatetimeIndex` where a figure generated by them is not pickleable (:issue:`18439`)
 -
 -
 

Original file line number	Diff line number	Diff line change
`@@ -93,7 +93,7 @@ I/O`
`93`	`93`	`Plotting`
`94`	`94`	`^^^^^^^^`
`95`	`95`
`96`		`--`
	`96`	+- Bug in ``DataFrame.plot()`` and ``Series.plot()`` with :class:`DatetimeIndex` where a figure generated by them is not pickleable (:issue:`18439`)
`97`	`97`	`-`
`98`	`98`	`-`
`99`	`99`