Update README.md

Author: yohsii

README.md

@@ -3,6 +3,8 @@ NOTE: this is an asp.net core migration of the mvc 5 project which you can find
 # puck cms
 Fast, scalable, code-first, unobtrusive and extensible with powerful querying and Lucene integration.
 
+[![Build status](https://ci.appveyor.com/api/projects/status/7d984nlou8fxw0hq?svg=true)](https://ci.appveyor.com/project/yohsii/puck-core)
+
 [Wiki](https://github.com/yohsii/puck-core/wiki)
 
 **why use puck**