Add Appveyor Status badge

README.md

@@ -2,7 +2,8 @@ labelme: Image Annotation Tool with Python
 ==========================================
 
 [![PyPI Version](https://img.shields.io/pypi/v/labelme.svg)](https://pypi.python.org/pypi/labelme)
-[![Build Status](https://travis-ci.org/wkentaro/labelme.svg?branch=master)](https://travis-ci.org/wkentaro/labelme)
+[![Travis Build Status](https://travis-ci.org/wkentaro/labelme.svg?branch=master)](https://travis-ci.org/wkentaro/labelme)
+[![Appveyor Build status](https://ci.appveyor.com/api/projects/status/epxf9b6c47cw373y/branch/master?svg=true)](https://ci.appveyor.com/project/wkentaro/labelme/branch/master)
 [![Docker Build Status](https://img.shields.io/docker/build/wkentaro/labelme.svg)](https://hub.docker.com/r/wkentaro/labelme)