use Devel::CodeObserver 0.11's interface
Checking in changes prior to tagging of version 0.23.

Changelog diff is:

diff --git a/Changes b/Changes
index efe0376..bf2ed75 100644
--- a/Changes
+++ b/Changes
@@ -2,6 +2,10 @@ Revision history for Perl extension Test-Kantan

 {{$NEXT}}

+0.23 2014-03-10T01:54:36Z
+
+    - use Devel::CodeObserver 0.11
+
 0.22 2014-03-10T01:18:39Z

     - use Devel::CodeObserver