Checking in changes prior to tagging of version 0.57.

Changelog diff is:

diff --git a/Changes b/Changes
index e61ba47..b24dc24 100644
--- a/Changes
+++ b/Changes
@@ -1,6 +1,8 @@
 Revision history for Perl extension CGI::Header.

-  - CGI::Header::Standalone was separated into CGI::Header::Adapter
+0.57 (1.00-RC10) Jun 1st, 2013
+
+  - CGI::Header::Standalone is separated into CGI::Header::Adapter
     and Apache2. Apache1 is not available at this time.

 0.56 (1.00-RC9) May 31st, 2013