Merge pull request encode#3229 from charettes/3.2-announcement-typo

Fixed a small typo in the 3.2 release announcement.

Author: jpadilla

docs/topics/3.2-announcement.md

@@ -74,7 +74,7 @@ The upshot is this: If you have many to many fields in your models, then make su
 
 ### List fields and allow_null
 
-When using `allow_null` with `ListField` or a nested `mant=True` serializer the previous behavior was to allow `null` values as items in the list. The behavior is now to allow `null` values instead of the list.
+When using `allow_null` with `ListField` or a nested `many=True` serializer the previous behavior was to allow `null` values as items in the list. The behavior is now to allow `null` values instead of the list.
 
 For example, take the following field: