add appveyor badge

alimanfoo · alimanfoo · commit 30ba89f0030a · 2016-09-18T20:20:10.000+01:00
diff --git a/README.rst b/README.rst
@@ -5,3 +5,6 @@ TODO
 
 .. image:: https://travis-ci.org/alimanfoo/numcodecs.svg?branch=master
     :target: https://travis-ci.org/alimanfoo/numcodecs
+
+.. image:: https://ci.appveyor.com/api/projects/status/r35av34952d9fcyn?svg=true
+    :target: https://ci.appveyor.com/project/alimanfoo/numcodecs
