fix whatsnew typo

Author: wholmgren

docs/sphinx/source/whatsnew/v0.2.1.txt

@@ -3,7 +3,7 @@
 v0.2.1 (July 13, 2015)
 -----------------------
 
-This is a minor release from 0.2.1. It includes a large number of bug fixes
+This is a minor release from 0.2. It includes a large number of bug fixes
 for the IPython notebook tutorials.
 We recommend that all users upgrade to this version.