Checking in changes prior to tagging of version 0.43.

Changelog diff is:

diff --git a/Changes b/Changes
index 16e355f..8be48b4 100644
--- a/Changes
+++ b/Changes
@@ -1,5 +1,7 @@
 Revision history for Perl extension CGI::Header.

+0.43  Apr 8th, 2013
+
    [INCOMPATIBLE CHANGES]

     - Remove dispatch tables used by set() and delete()
revise new() entirely