update docs
Checking in changes prior to tagging of version 0.12.

Changelog diff is:

diff --git a/Changes b/Changes
index e818a16..2d587a2 100644
--- a/Changes
+++ b/Changes
@@ -2,6 +2,11 @@ Revision history for Perl extension WWW-Form-UrlEncoded

 {{$NEXT}}

+0.12 2014-02-18T03:38:24Z
+
+    - install .keep file under $arch/WWW/Form/UrlEncoded/XS to keep compatiblity before 0.10
+    - build_urlencoded supports arrayref and hashref args
+
 0.10 2014-02-17T06:10:58Z

     - [IMPORTANT] split WWW::Form::UrlEncoded into another dist.