readme: remove AppVeyor badge

Use Travis CI for Windows #284
diff --git a/README.md b/README.md
index 3993207..f7e67db 100644
--- a/README.md
+++ b/README.md
@@ -14,7 +14,7 @@
 |----------|----------|----------|
 |inotify   |Linux 2.6.27 or later, Android\*|Supported [![Build Status](https://travis-ci.org/fsnotify/fsnotify.svg?branch=master)](https://travis-ci.org/fsnotify/fsnotify)|
 |kqueue    |BSD, macOS, iOS\*|Supported [![Build Status](https://travis-ci.org/fsnotify/fsnotify.svg?branch=master)](https://travis-ci.org/fsnotify/fsnotify)|
-|ReadDirectoryChangesW|Windows|Supported [![Build status](https://ci.appveyor.com/api/projects/status/ivwjubaih4r0udeh/branch/master?svg=true)](https://ci.appveyor.com/project/NathanYoungman/fsnotify/branch/master)|
+|ReadDirectoryChangesW|Windows|Supported [![Build Status](https://travis-ci.org/fsnotify/fsnotify.svg?branch=master)](https://travis-ci.org/fsnotify/fsnotify)|
 |FSEvents  |macOS         |[Planned](https://github.com/fsnotify/fsnotify/issues/11)|
 |FEN       |Solaris 11    |[In Progress](https://github.com/fsnotify/fsnotify/issues/12)|
 |fanotify  |Linux 2.6.37+ | |