Checking in changes prior to tagging of version 0.20.

Changelog diff is:

diff --git a/Changes b/Changes
index 5b685ee..4352efa 100644
--- a/Changes
+++ b/Changes
@@ -2,6 +2,10 @@ Revision history for Perl module Plack::Middleware::ServerStatus::Lite

 {{$NEXT}}

+0.20 2013-08-27T00:17:34Z
+
+   - Reformatted Changes file as per CPAN::Changes::Spec (Thank you neilbowers)
+
 0.19 2013-08-26T05:03:32Z

    - add warnings when 'allow' is missing.