[3.1] Updates Changelog

Changelog

@@ -25,14 +25,32 @@ new in Celery 3.1.
 
     Fix contributed by Maxime Verger.
 
+- **Task**: An exception is now raised if countdown/expires is less
+  than -2147483648 (Issue #3078).
+
 - **Programs**: :program:`celery shell --ipython` now compatible with newer
   IPython versions.
 
+- **Programs**: The DuplicateNodeName warning emitted by inspect/control
+  now includes a list of the node names returned.
+
+    Contributed by Sebastian Kalinowski.
+
+- **Worker**: Node name formatting now emits less confusing error message
+  for unmatched format keys (Issue #3016).
+
 - **Results**: amqp/rpc backends: Fixed deserialization of JSON exceptions
   (Issue #2518).
 
     Fix contributed by Allard Hoeve.
 
+- **Prefork pool: The `process inqueue damaged` error message now includes
+  the original exception raised.
+
+- **Documentation**: Includes improvements by:
+
+    - Jeff Widman.
+
 .. _version-3.1.20:
 
 3.1.20