Add ``start nonexistant:*`` fix to changelog

CHANGES.txt

@@ -32,7 +32,7 @@
   commands in ``supervisorctl``.  Patch by Brent Tubbs.
 
 - The ``status`` command in ``supervisorctl`` now supports group name
-  syntax: ``status groupname:*``.
+  syntax: ``status group:*``.
 
 - Fixed an XML-RPC bug where calling supervisor.clearProcessLogs() with a
   name like "group:*" would cause a 500 Internal Server Error rather than
@@ -41,6 +41,11 @@
 - Tab completion in ``supervisorctl`` has been improved and now works for
   more cases.  Thanks to Mathieu Longtin and Marc Abramowitz for the patches.
 
+- Attempting to start or stop a process group in ``supervisorctl`` with the
+  ``group:*`` syntax will now show the same error message as the ``process``
+  syntax if the name does not exist.  Previously, it would show a Python
+  exception.  Patch by George Ang.
+
 3.0 (2013-07-30)
 ----------------