Added Amon2::Web::Disptacher::RouterBoom#delete_

I need to use DELETE method for AngularJS.
Checking in changes prior to tagging of version 5.13.

Changelog diff is:

diff --git a/Changes b/Changes
index 305fc30..bc4a677 100644
--- a/Changes
+++ b/Changes
@@ -1,5 +1,10 @@
 {{$NEXT}}

+5.13 2013-10-29T02:10:40Z
+
+    - Web::Disptacher::RouterBoom supports DELETE method.
+      (tokuhirom)
+
 5.12 2013-10-28T06:55:00Z

     - Trivial setup script changes.