Fix typo in README

Author: bluss

README.rst

@@ -96,7 +96,7 @@ Recent Changes (ndarray)
 - 0.6.8
 
   - Fix a bug in a partially consumed elements iterator's ``.fold()``.
-    (**Note** that users are recommended to use not use the elements iterator,
+    (**Note** that users are recommended to not use the elements iterator,
     but the higher level functions which are the maps, folds and other methods
     of the array types themselves.)